g20110245/edats: oedo-2011-0255- response email re: action: … · 2012. 12. 5. · attachments:...

1
From: Abu-Eid, Boby To: Williams, Shawn ; Rodriguez, Sandra ; Fleming, Barbara ; FSME_TicketCloseouts Resource Cc: Felsher, Harry ; Miller, Debra ; Camper, Larry ; Cool, Donald ; Persinko, Andrew ; Davis, Catherine ; Deegan, George ; Schwartzman, Jennifer Subject: Action: Input to Close Ticket # G20110245 Date: Tuesday, August 16, 2011 10:17:00 AM Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245 Re-Draft DS357.pdf EDO Incoming Control DS357 MemberState Revie Ticket G20110245.pdf ds357.pdf Shawn, Please find attached USA Member State Coordinated Comments on IAEA Draft Safety Guide titled: “Monitoring and Surveillance of Radioactive Waste Disposal Facilities.” The attached comments represent coordinated review inputs received from Federal Agencies through ISCORS (only DOE provided comments) and from NRC Offices. The attached input should complete all tasks under Ticket #G20110245. Please note that the Final Official Member State Comments on DS357 must be received by IAEA on August 30 th , 2011. If you have any questions or remarks on the attached comments please let me know. Please note Boby Sandra, Based on the above e-mail and attached comments, please close Ticket #G20112045. Please incorporate in ADAMS Package the attached comments and the attached incoming materials (e.g.; G20110245 Ticket; EDO Incoming Control; and PDF file of the reviewed IAEA Document DS357). Your prompt action is appreciated as this ticket is due today. Boby

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Page 1: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

From Abu-Eid BobyTo Williams Shawn Rodriguez Sandra Fleming Barbara FSME_TicketCloseouts ResourceCc Felsher Harry Miller Debra Camper Larry Cool Donald Persinko Andrew Davis Catherine Deegan

George Schwartzman JenniferSubject Action Input to Close Ticket G20110245Date Tuesday August 16 2011 101700 AMAttachments USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Finaldoc

TicketG20110245 Re-Draft DS357pdfEDO Incoming Control DS357 MemberState Revie Ticket G20110245pdfds357pdf

ShawnPlease find attached USA Member State Coordinated Comments on IAEA Draft Safety Guide titledldquoMonitoring and Surveillance of Radioactive Waste Disposal Facilitiesrdquo The attached commentsrepresent coordinated review inputs received from Federal Agencies through ISCORS (only DOEprovided comments) and from NRC Offices The attached input should complete all tasks underTicket G20110245 Please note that the Final Official Member State Comments on DS357 must be

received by IAEA on August 30th 2011 If you have any questions or remarks on the attachedcomments please let me know Please noteBoby SandraBased on the above e-mail and attached comments please close Ticket G20112045 Pleaseincorporate in ADAMS Package the attached comments and the attached incoming materials (egG20110245 Ticket EDO Incoming Control and PDF file of the reviewed IAEA Document DS357)Your prompt action is appreciated as this ticket is due todayBoby

USA Comments on IAEA Safety Guide DS357 Monitoring and Surveillance of Radioactive Waste Disposal Facilities

COMMENTS BY REVIEWER

Reviewer USA (Contact Boby Abu Eid US NRC)

CountryOrganizations USANRC amp DOE Date 08162011

RESOLUTION

Comment No

ParaLine No

Proposed new textComment

Reason

Accepted

Accepted but modified as follows

Rejected

Reason for modificationrejection

1

Overall

DS357 Draft Guide is a very useful document and relevant to the intended scope and objective It covers a wide range of topics and overlapping programs and activities The US appreciates the opportunity to offer ldquoGeneralrdquo and ldquoSpecificrdquo comments presented below to enhance the document for completeness consistency and presentation

Relevance and usefulness

GENERAL COMMENTS

2

General

The scope of the draft guide is somehow inconsistent with the definitions of ldquomonitoringrdquo and of ldquosurveillancerdquo in that it includes (and has as its primary focus) significant aspects of site characterization As stated in Para 21 the BSS definition of ldquomonitoringrdquo is ldquoThe measurement of dose or contamination for reasons related to the assessment or control of exposure to radiation or radioactive substances and the interpretation of the resultsrdquo Para 26 states that for purposes of this guide the term surveillance refers to ldquoThe physical inspection of a waste management facility in order to verify its integrity to protect and preserve passive barriersrdquo Thus neither of these definitions includes site characterization to establish a safety case for a licensing process

However the utility of coordinating monitoring and surveillance guidance with site characterization activities is apparent For example many of the parameters which are measured before site construction to establish a baseline for monitoring are also needed for site characterization activities Nonetheless the traditional distinction between monitoring surveillance and site characterization should be maintained

Therefore it is desired to retain

the discussions of site characterization however the issue of overlap and incorporation of site characterization topic in monitoring needs to be addressed One option is to discuss characterization aspects in more detail and modify the title of the guide to include ldquomonitoring surveillance and characterizationrdquo Alternatively clear distinction between the three activities needs to be recognized and delineated in the text (See also specific comments for details)

Clarity Overlap and distinction between characterization activities and activities belonging to monitoring and surveillance

3

General

The document lacks key aspects of safety and security integration and alignment particularly for the surveillance program in general and the monitoring program under specific emergency conditions For example surveillance for site access and potential intrusions (eg intentionalinadvertent) aspects were disregarded in the document We believe this is an important aspect involving integration of safety and security which needs to be addressed and discussed in some detail In addition specific details regarding control and deterioration of fences barriers and security needs are lacking

Completeness The document needs to address integration and alignment of safety and security aspects pertaining to generic surveillance program and specific monitoring particularly under emergency conditions

4

General

Monitoring and Surveillance under Emergency Conditions

The document presented a brief Section (Para 614 and 615) on ldquoMonitoring for Emergency Responserdquo In addition surveillance under emergency conditions was hardly addressed We believe these topics are quite significant and need to be expanded and addressed in more detail In this context the document could benefit from experience gained from previous accidents particularly recent Fukushima Japan accident in relation to the needs for monitoring to protect workers the public and the environment particularly from off-site releases

The document mentions responsibilities of the ldquoOperatorrdquo for reporting monitoring and surveillance to the regulatory body periodically and reporting unexpected or emergency circumstances This topic should be discussed further in more detail

Remote technology approaches and methods for surveillance and monitoring under sever emergency situation is also a significant topic to discuss in relation to development of surveillance and monitoring programs Further off-site and beyond boundary surveillance and monitoring including communication and collaboration with stakeholders need to be addressed

The document should also address security and emergency response as examples of where the delegation of authority may be considered to other agencies

In brief the document needs to ensure that emergency preparedness management and arrangements are in place and are routinely tested

Completeness The document needs to address monitoring and surveillance aspects under severe emergency conditions in more detail

5

General

The document lacks organization and consistency in contents and presentation

Considering contents aspect for example Chapter 7 on ldquoDevelopment and Implementation of a Surveillance Programrdquo lacks detailed aspects in terms of waste inventory site intrusion location and frequencies of surveillance criteria for performance of barriers and assessment of safety functions in relation to the safety case and the surveillance and monitoring programs In addition the document lacks significant aspects pertaining to audits and QAQC to assess surveillance and monitoring results

Another example is Chapter 9 ldquoManagement Systemrdquo which lacks specifics regarding decision-making and interactions between licensees operators regulators and stakeholders regarding design and implementation of surveillance and monitoring programs Such interactions and communication are necessary during interpretation of data and assessment of results pertaining to safety functions Further financial assurance issues were not discussed in order to facilitate long-term monitoring corrective actions and maintenance of the disposal facility

In terms of organization and consistency the document needs to be consistent in use of the terms and to delineate specific areas and responsibilities of overlapping programs

The document presentation can be improved by considering use of a general bullet system across the entire document It can also be improved in use of acronyms by

a Considering including a list of acronyms in the document Example Para13 NORM

b A consistent approach to spelling out acronyms at first usage in the document is suggested Several acronyms are used and then spelled out in the text later

(see also specific comments)

Completeness Quality Consistency Clarity and Edit

Organization and consistency in content format and presentation and appropriate edit of document

6

General

The document needs to update the reference list and use updated references in citation For example the document should refer to the updated BSS safety requirements (DS379) and the updated safety case guidance (DS355)

Completeness and quality to update cited references

SPECIFIC COMMENTS

1

14 ln 10

Page 1

Revise sentence to read as follows ldquoThe monitoring and testing programs that are needed to establish baseline conditions and to inform operational management decisions should be put in place during this periodrdquo

Completeness It is worthwhile to include establishing baseline conditions based on site characterization data as this is an important aspect of initial monitoring

2

14 last bullet ln 10

Page 2

Change ldquowillrdquo to ldquomayrdquo

The time of license termination may be different for different regulatory schemes

3

15 ln 4

Page 2

Delete ldquotherdquo before ldquobasic requirementsrdquo

The BSS is not the only source of such requirements and all countries do not use the BSS as the basis for their requirements

4

111 ln 1-2

Page 4

Revise the first sentence to read ldquoThis Safety Guide emphasizes integration of monitoring and surveillance with site characterization activities needed for development of the safety caserdquo

Consistency with the definitions of monitoring and surveillance

5

24 p 5

412 p 14

63 p 21

87 p 32 and

I-5 p 40

The document appears to have a mix-up between monitoring and characterization

For example the section on ldquoPre-Operational Period Monitoringrdquo belongs to site characterization Therefore we recommend having an independent Section on ldquoPre-Operational Site Characterizationrdquo and incorporation of 63 through 66 and other related texts) under this Section It should be noted that one purpose of the pre-operational site characterization is to establish baseline and natural background conditions at the site

Distinction between monitoring and characterization

Monitoring is defined in Section 23 as ldquo Continuous or periodic observations and measurements of environmental engineering or radiological parametersrdquo Most if not all of the activities related to ldquoPre-Operational Period Monitoringrdquo are indeed site characterization activities and are neither continuous nor periodic Therefore what is being described is site characterization Characterizing a site is NOT the same as monitoring a site though characterization data can be used to establish baseline conditions

6

24

Page 5

Move Para 24 to become Para 22 and revise the first sentence to read ldquoMonitoring involves many activities including coordination with site characterization activities and use of characterization data as practicablerdquo Add a new second sentence ldquoTherefore the integration of these activities is discussed in this guiderdquo

Consistency with the definitions of monitoring and surveillance

7

212 p 6

Para 212 brings up an important issue pertaining to evolution of the site characterization phase into the monitoring and surveillance programs The concluding statement made in Para 212 p 6 ldquoAs a result provision should be made to anticipate the needs of monitoring at later periods of the facility lifetime and to gather monitoring data that informs later planning and actionsrdquo is important and should be discussed in more detail particularly on the use of characterization data to design and plan for monitoring

This topic should be expanded with illustrated examples and more elaboration

The document needs to have more elaboration clarification and explanation of the role of characterization in planning of monitoring and surveillance programs

8

216 ln 6

Page 7

Revise sentence to read as follows ldquohellipto build confidence that each barrier and its associated safety function(s)helliprdquo

It seems more appropriate to state that ldquobuilding confidencerdquo in barriers or safety functions performance through monitoring rather than ldquoensuringrdquo performance as ldquoensuring aspectsrdquo are difficult tasks to meet

9

217 ln 3

Page 7

Replace ldquosocial aspectsrdquo with a more descriptive term such as ldquostakeholdersrsquo feedbackrdquo

Language Using the term ldquosocial aspectsrdquo is inappropriate and does not reflect the intended purpose and meaning of the sentence

10

32 c)

Page 9

Revise sentence to read as follows ldquohellipand coordinate those plans with responsible authorities that should be involved under emergency conditions as well as offsite respondersrdquo

To ensure coordination with responsible authorities andor agencies under emergency situation and with responders

11

38 p10

Suggest deleting first sentence ldquoIf the potential exists for an accidenthelliprdquo and revising second sentence

Our suggestion to delete or revise this phrase because it is not whether or not the potential for an accident exists that is important (there is always potential for some type of accident) but the likelihood of an accident to occur

Clarity and correctness

The first sentence of Sec 38 seems to be unrelated to the rest of the paragraph

12

Chapter 4

Suggest adding a paragraph on selection of monitoring locations with illustrative example (possibly between 49 and 410) The suggested Para is given below

ldquoThe monitoring locations should be chosen in a way that reduces uncertainty in the spatial correlation of parameters to acceptable levels so that a high degree of confidence will result from the flow and transport modeling This can be determined by various statistical methods For example groundwater monitoring wells are usually assigned in the following critical locations

1) Source areas within and immediately down-gradient of source area

2) Transmissive zones with highest contaminant concentrations or hydraulic

conductivity

3) Fringe portions and boundary of the plume

4) Areas representative of contaminated and uncontaminated geochemical settings

5) Areas supporting the monitoring of site hydrogeology or

6) Regulatory points of compliancerdquo

Completeness and Clarification

13

Chapter 4

Suggest adding paragraph on monitoring frequency as given below

ldquoThe appropriate monitoring frequency can be determined based on the predicted rate with which contaminant concentrations change due to parameters such as groundwater flow and natural attenuation processes the degree to which the causes of this variability are known the types of evaluations to be performed the locations of possible receptors and the remedial action objectives for the site In situations where the hydrologic geochemical and contaminant trends are stable and the conceptual site model is verified by existing monitoring data reductions in sampling frequency may be warranted In situations where the variability is high increases in monitoring frequency may be warranted For example more frequent monitoring of groundwater elevations may be warranted particularly during the establishment of baseline conditions to improve the characterization of groundwater flow patterns The other factors for determining monitoring frequency include the relevance of performance indicators and the information redundancy If a performance indicator is not expected to significantly influence the performance assessment of a site then monitoring frequency for that indicator could be greatly reduced or even eliminated If over a period of several years the data trends appear to be stable a reduction in monitoring frequency may be warrantedrdquo

Completeness and Clarification

14

48 line 3

Page 14

Add ldquoas well as for geologic repositoriesrdquo

Completeness The results of monitoring are also important and applicable for all repositories

15

410

Page 14

Consider using the following sentence ldquo Monitoring programmes should include activities to update and refurbish monitoring technology when possible and when warrantedrdquo

Monitoring systems may over time degrade and technology improves

16

411

Page 14

Add following two sentences to the end of the paragraph ldquoIt is also important when considering monitoring of a given parameter to clearly understand and communicate to the regulator and stakeholders what type of results would be expected and how the monitoring results will be interpreted It is also recommended to provide ranges of expected values to assess uncertaintiesrdquo

These aspects are especially important when considering relatively new monitoring techniques for performance confirmation that may require some interpretation to explain the significance of a given result It also ensures that prior to carrying out monitoring careful consideration would be given to what will be expected with consideration of uncertainties

17

412

Revise the first sentence to read ldquoThe general objective of monitoring programs during the preoperational period is to establish pre-existing levels of contaminants and to establish a baseline for consistency with the definition of monitoring and to identify parameters that may be indicative of performance in the post closure period It is noted that site characterization programs typically establish site natural characteristics of features events and processeshelliprdquo

Completeness and explanation of the role of site characterization

18

413 p 16

The sentence in Para 413 ldquoThe duration of post-closure monitoring should also depend on reasonable assumptions on the duration of institutional stability and continuity of knowledge and its consequent ability to ensure ongoing monitoring and maintenancerdquo is vague and ambiguous It is unclear of what is meant by ldquoinstitutional stabilityrdquo and the criteria to assess such stability It is also unclear of necessary actions to take in order to assess duration of post-closure monitoring

Clarification and addressing ambiguity regarding duration of post-closure period

19

Sec 415 p16

Verb tense

Grammar In second sentence ldquocarriedrdquo should be ldquocarriesrdquo

20

Sec 417 p 16

Para 417 p 16 states ldquoAs appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programrdquo

An example should be given of how failure is accounted for in design of monitoring

Clarification

21

423

Page 17

Add the following bullet ldquoEstablishing process to verify the qualification and certifications for vendor laboratories

Need to confirm that laboratories doing sample testing are certified and acceptable to regulators Part of 411 ldquoindependent verification of valuesrdquo

22

Sec 423

It is necessary that the bullet points presented under Para 423 be discussed with more elaboration and with some illustrative examples Certain points donrsquot appear to be covered in the text For example identification of monitoring locations and decommissioning of monitoring instrumentation were not addressed These points represent significant aspects of the monitoring program and needs further elaboration and discussion in either Chapter 4 or Chapter 5

Completeness

23

423

Page 17

Add the following bullet ldquoEstablishing independent assessment processes for the monitoring programrdquo

Part of 411 ldquoindependent verification of valuesrdquo

24

Chapter 5

pp 19 - 20

Suggest removing Chapter 5 and incorporating its essential content into Chapter 4

Chapter 5 does not provide substantive monitoring information or independent topics related to monitoring to justify as an independent Chapter The information provided in Chapter 5 can be easily incorporated into Chapter 4

25

52 amp 54

Pages 19 amp 20

Para 52 regarding near surface disposal discussion is inconsistent with Para 54 mining residue disposal It should be noted that mining residues are frequently disposed of in near surface facilities and practical considerations dictate that they will continue to be Thus near surface facilities are typically used to provide isolation for substantially longer time period than the period given in the document ldquoa few hundred yearsrdquo

Clarification and consistency

26

62

Page 21

Delete the last bullet ldquoProvision of an environmental databaserdquo

Redundancy with the first bullet ldquoBaselinerdquo

27

67 ln 9

Page 23

Revise the first bullet as follows ldquo Data for the as-built properties of materials and structures and for confirmation of the performance of elementshelliprdquo

Clarity and completeness An important aspect of operational monitoring is to confirm the as-built properties of materials and structures important to safety functions as compared to what was assumed in the safety assessment

28

69 Line 4 of Page 24

ldquo envisaged including area-wide events (earthquakes cyclones) that may impact access and offsite supportrdquo

All reinforced by recent earthquake in Japan an area-wide event can prevent offsite assistance being available and limit worker access to site

29

71 p 27

Para 71 p 27 states ldquoThe surveillance program also includes review and assessment of records trends and performance of different parametersrdquo Assessment of performance sounds very much like ldquoPerformance Assessment (PA)rdquo The definition provided on pp 5-6 states that ldquoIn the context of this Safety Guide the term surveillance refers to The physical inspection of a waste management facility in order to verify its integrity to protect and preserve the passive safety barriersrdquo

Based on the above statement there appear to have an overlap and mix-up between surveillance from one side and monitoring PA and inspection amp corrective actions on the other If the surveillance program is not limited to inspections the definition of level of surveillance should be defined and the distinction between surveillance and monitoring should be made clear

Either change sentence quoted or change definition of surveillance

Overlap and mix-up between surveillance and Performance Assessment and Inspection

30

74 p 27

Delete Para 74 p 27 which states ldquoThe monitoring and testing programme should start in the pre-operational period during construction to allow detection of early degradation of the components integrity or to find out the quality of the host rock around the excavationsrdquo

The meaning of this statement is unclearrdquo As discussed above the pre-operational period surveillance is synonymous to site characterization

Redundancy amp Terminology

31

76 p 28

This Section only discusses duration period after closure exclusively The Section does not describe what actual surveillance activities need to be performed Therefore it is necessary to provide a list of surveillance activities under this Section to present adequate information describing what surveillance activities need to be performed

Completeness

32

711 ndash 716

Page 29

Delete the title ldquoDetailed inspectionsrdquo In the first line of Para 712 delete ldquodetailedrdquo Also delete Para 714 and 716

It is unclear as to what the difference is between ldquoroutinerdquo and ldquodetailedrdquo inspections Therefore the document needs to discuss and identify the difference between ldquoRoutinerdquo and ldquoDetailedrdquo inspections

Clarity and completeness The difference between ldquoroutinerdquo and ldquodetailedrdquo inspections is ambiguous and apparently indistinct A single statement that inspectors should be qualified is adequate enough

33

81 ln 2

Page 31

Revise sentence to read as follows ldquohellipfor the purpose of building confidence in safety of disposal facilities and reduction of risk or uncertaintyhelliprdquo

Emphasize the overall goal of monitoring which is to build confidence and confirmation of safety functions and to reduce risk

34

82 p 31 and 92 p 35

The document uses in Para 82 amp 92 the term ldquolifetimerdquo in reference to life of facility which seems to have different connotation In 82 ldquolifetimerdquo seems to include an indefinite far future period while in 92 it seems to only include a period during which active decision-making would still be occurring Therefore the document needs to address consistency in use of this term

Consistency in meaning and use of terms

35

83

Page 31

Include sentence at end ldquoPrior to monitoring the potential spatial and temporal variability of the data to be collected and how it will be interpreted should be well understood and explained to stakeholdersrdquo

Setting reasonable expectations for monitoring is important

36

87

Page 32

Consider re-editing paragraph 87

1 Complete paragraph to read ldquoExisting monitoring and surveillance data from comparable types of facilities should also be collected and evaluated during the pre-operational period This will facilitate the development of monitoring and surveillance programs for the new site Comparisons of operating records at nearby facilities can also provide information on the technology used at these equivalent facilities which can aid in establishing proper safety functions and sustainability requirements for the new disposal facilityrdquo

2 Delete the last sentence of 87

3 We note that this section has a number of good ideas and is important to be elaborated on in the document Therefore this section should be enhanced by including some examples to link monitoring during the different stages to assumptions made in a safety assessment and the anticipated performance of the barriers and safety functions A good example of topic which can be discussed further is the ldquoas-built conditions and performance of disposal system componentsrdquo In addition we suggest rewording 87 to address the use of baseline data to establish confidence in performance of the system

EditorialCompleteness

While useful to support the safety case compiling existing data from other facilities is not actually an essential segment of monitoring surveillance or site characterization according to the definitions of those terms Regarding the third sentence the records of facilities which have been operated for only a few decades cannot provide sufficient confidence that a similar facility will perform in a similar manner for hundreds or thousands of years

For completeness more elaboration and discussion with illustrative examples are necessary

37

Before 88

Page 32

It would be beneficial to add a paragraph before 88 to highlight the importance of ldquomonitoringrdquo during the construction phase During this phase the emphasis is on confirming as-built conditions to be consistent with assumptions in the safety assessment The importance of identifying ranges of expected ldquoas-builtrdquo conditions should also be emphasized

Confirmation of as-built conditions compared to assumptions in the safety assessment is a critical activity relevant to safety functions and is worth emphasizing in this section Use of ranges of values are important in order to avoid a situation of defending

measurements in consideration of ldquoexpectedrdquo point values

38

88 p 32

It is unclear if ldquoperformance confirmation programrdquo is synonymous with ldquomonitoring and surveillance programrdquo or something different that needs to be defined and discussed In this context the performance confirmation programrdquo needs to be discussed in some detail

Clarification Discussion and definition of the ldquoPerformance confirmation programldquordquo and how it is related to ldquomonitoring and surveillance programrdquo if indeed it is an independent program

39

812

Page 34

Add sentence ldquoSuch communication needs to begin early in the process it is generally easier to explain potential uncertainties before beginning of the monitoring program than trying to provide an explanation after monitoring beginsrdquo

This emphasizes the need to communicate expected monitoring results and uncertainties early before start of monitoring

40

813 p 34

Rewrite Section 813

The meaning or purpose of this section is not clear

41

815 ln 4

Page 34

Modify sentence to read ldquohellipincreased sampling frequency for indentifying andor confirming spatial and temporal trendshelliprdquo

Clarification It is significant to clarify that understanding trends is important and such trend can be both spatial and temporal

42

91

First Bullet

Page 35

Comment

It should be noted that it may be neither feasible nor necessary for national government agencies to make special provisions for ensuring continuity of resources for tens or hundreds of years In fact private companies are frequently the responsible party to ensure resources for waste disposal sites The regulators can demand financial surety as a licensing requirement Nevertheless ultimate Government ownership and responsibility is a durable institutional control and constitutes the requisite provision of resource availability

Correctness and clarification

43

95 Line 3

Page 36

ldquoand since and surveillancerdquo

Edit

44

Annex I

Annex I Title ldquoExamples of Monitoring and Surveillance Information Collected for a Geological Disposal Programrdquo However the scope of the safety guide covers a variety of radioactive waste disposal facilities It is unclear if the scope of this Annex would apply in general to all disposal facilities or just to geological disposal facilities or to radioactive waste facilities in general

Clarification in scope and application of Annex I

45

Annex I

Page 43

Very little mention of geophysical methods implied or explicitly stated as useful in text Paragraph I-14 mentions boreholes but geophysical methods of monitoring changes in barriers and characterizing of ambient conditions are often very important

Completeness

46

Annex I

Table I-1

Page 45

General comment on Table I-1

More clarity is necessary and inconsistencies within the Table need to be reconciled Examples

a Nearly all items in first part of Table I-1 should be checked for the pre-operational phase since those types of data and information would be

Needed Need to check the main sentences which will include all bullets

b We recommend that the generic approach to Table organization be based on phases of facility development (eg site selection facility construction operation closure and post-closure periods) considering time sequence

Table I-1 does not seem to be organized properly Suggest formatting the Table andor its re-organization as suggested in the comments

47

Table I-1 p 45

Table I-1 appears to be missing sections or activities on the following topical areas

middot Chemical and physical changes to the surrounding geo-sphere and in the atmosphere and

middot Radionuclide release detection (measuring radioactivity)

We suggest including the above missing sections

Completeness

48

Para I-18

Add a bullet

ldquochanges to the flood plain and the magnitude of the 100-year floodrdquo

Many of the bullet items in this paragraph contain items that might affect flooding (eg land use drainage slope evolution etc) ndash it seems that flooding could be quite important for certain facilities and it may be useful to have some flooding parameters directly noted in this list

Completeness

49

Annex II

Para II-1 through II-8 and title

Page 51

Considering site description presented in Para II-1 through II-8 the site appears to incorporate significant waste storage aspects Therefore based on apparent use of the site for ldquostorage and disposalrdquo we recommend that Annex II title be modified to indicate ldquoNEAR SURFACE STORAGE AND DISPOSAL PROGRAMrdquo

The items are presented as the intent is temporarily storage of waste in bunkers or holes and therefore closurepost-closure may not be expected pending on the outcome of monitoring or waste management decisions In addition the Annex uses the term ldquostorage wellsrdquo which seems to indicate that it is intended for storage or for dual purpose storage amp disposal This ambiguity and overlap between ldquostoragerdquo and ldquodisposalrdquo needs to be addressed and clarified

Need to address and resolve ambiguity to clarify purpose and intent of the site regarding storage (short-termlong-term) and permanent disposal

50

Annex II

Para II-2 line 2

Page 51

ldquoQuaternary rocksrdquo should read Quaternary sediments or Quaternary units

To avoid implication that the units are indurate and rock-like since it appears as if they are unconsolidated sediments Paragraph should also make clear that the units are generally unsaturated

51

Annex II

pp 51-59

The example presented in Annex II does not demonstrate significant aspects and key components of the surveillance and monitoring programs discussed in the document For example i) the different phases of operation and post-closure are ignored ii) the uses of the listed monitoring activities as described in detail in Chapter 8 of the document are not included and iii) surveillance is not part of the this ldquomonitoring and surveillance examplerdquo In addition The ldquoType of Monitoringrdquo column only has two types environmental and source Both types are defined in Chapter 2 as measuring activity or external dose rates respectively However many of the properties listed on page 58 are neither activity nor dose rates Matter of fact most of the properties listed in Annex I are not activity or dose rates (eg chemistry stresses head etc) but then Annex II goes on to minimize monitoring these properties

Scope purpose consistency and completeness of of Annex II

52

Annex II

Figure II-1

Page 52

The section needs clarification

Figure II-1 requires

a North arrow some grayscale lettering and lines and keys are either not legible or out of focus

b The Table describes upstream and downstream and there is no indication of flow direction on map it could be useful to add to the Figure flow direction arrows or a contour or two

Incomplete amp Unclear Figure

53

Annex II

Page 53

a On page 53 line 1 remove ldquoIndash3rdquo from paragraph header ldquoEARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIESrdquo

b On page 53 line 5 from bottom Remove ldquoIndash4rdquo from paragraph header ldquoOPERATIONAL MONITORING AND SURVEILLANCErdquo

Editorial

Headers are incorrectly inserted or misplaced Unclear paragraph formatting

54

Annex II

Para II-13

Page 53

a First Bullet ldquoand in total 28 wells has beenrdquo should read ldquohave beenrdquo

b Last bullet ldquoInvolving the new rainwater collector basinrdquo the intent of this bullet is not entirely clear

c Was a new basin constructed Would it be clearer to revise bullet to read ldquoInvolving construction or monitoring of the new rainwater collector basinrdquo Consider revising bullets providing clarification of the intent of the bullets presented

Grammar amp Clarity

55

Annex II

Para II-16

Page 53

In II-16 rather than use of term ldquofirstrdquo using the term ldquoinitialrdquo may be more appropriate as Para II-19 also uses ldquofirstrdquo again in describing the chronology of safety assessment

Consistency

56

Annex II

Para II-21

Page 54

It is unclear whether ldquocorrective actionsrdquo were taken because of the probable leak (tritium in wells) or only further monitoring in accordance with a monitoring plan It is unclear of the purpose of having a new aerosol and soil sampling points as described in paragraph II-22 We suggest providing more discussion and clarification of tests enhancement as well as causes and effects on monitoring program tests and evolution

Clarification and completeness

57

Annex II

Para II-25

Page 54

Line 1 In place of ldquocomposed of work ofrdquo substitute with ldquoconducted byrdquo

Editorial

58

Annex II

Table II-1

Page 55

a Re-title to indicate ldquoSUMMARY OF STORAGE AND DISPOSAL MONITORING SYSTEMrdquo

b Vast majority of items indicated to be ldquoBASE LEVELrdquo Evaluation Base level implies pre-emplacementpre-disturbance Text indicates some radionuclide migration which would show disturbance Should the evaluation column indicate ldquobaselinerdquo and ldquooperational disturbancerdquo monitoring results both What is baseline vs base level as used in these tables and text

Completeness consistency and clarification

Page 2: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

Display Ticket

Ticket Type EDO - Green Ticketing Organization FSME

Ticket Number G20110245 Ticket Contact TBD

TAR N Ticket Created On 0407 2011

ADAMS Number Ticket Due Date 0816 2011

FOIA Number Ticket Extensions 0

WITS Ticket Number Ticket Status

Description IAEA DRAFT SAFETY GUIDE MONITORING AND SURVEILLANCE OFRADIOACTIVE WASTE DISPOSAL FACILITIES (DS 357) (DUE TO IAEA 83011)(EDATS OEDO-2011-0255)

Task Basis From Bruno to NRC dtd 32911

CorrespondenceOriginator

Correspondence To Routing Response Signatures Response To

Gerard Bruno NRC PolandTresslerDavisFleming

Shawn Williams

Special Instructions(Task 1)

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DS357

2011-03-15

IAEA SAFETY STANDARDS for protecting people and the environment

Monitoring and Surveillance of Radioactive Waste Disposal Facilities DRAFT SAFETY GUIDE

DS357

Draft Safety Guide

Action For submission to Member States for comment (Step 8)

IAEA SAFETY RELATED PUBLICATIONS

IAEA SAFETY STANDARDS

Under the terms of Article III of its Statute the IAEA is authorized to establish or adopt

standards of safety for protection of health and minimization of danger to life and property and to

provide for the application of these standards

The publications by means of which the IAEA establishes standards are issued in the IAEA

Safety Standards Series This series covers nuclear safety radiation safety transport safety and waste

safety and also general safety (ie all these areas of safety) The publication categories in the series

are Safety Fundamentals Safety Requirements and Safety Guides

Safety standards are coded according to their coverage nuclear safety (NS) radiation safety

(RS) transport safety (TS) waste safety (WS) and general safety (GS)

Information on the IAEArsquos safety standards programme is available at the IAEA Internet site

httpwww-nsiaeaorgstandards

The site provides the texts in English of published and draft safety standards The texts of safety

standards issued in Arabic Chinese French Russian and Spanish the IAEA Safety Glossary and a

status report for safety standards under development are also available For further information please

contact the IAEA at PO Box 100 A-1400 Vienna Austria

All users of IAEA safety standards are invited to inform the IAEA of experience in their use (eg

as a basis for national regulations for safety reviews and for training courses) for the purpose of ensuring

that they continue to meet usersrsquo needs Information may be provided via the IAEA Internet site or by

post as above or by e-mail to OfficialMailiaeaorg

OTHER SAFETY RELATED PUBLICATIONS

The IAEA provides for the application of the standards and under the terms of Articles III and

VIIIC of its Statute makes available and fosters the exchange of information relating to peaceful

nuclear activities and serves as an intermediary among its Member States for this purpose

Reports on safety and protection in nuclear activities are issued in other publications series in

particular the Safety Reports Series Safety Reports provide practical examples and detailed methods

that can be used in support of the safety standards Other IAEA series of safety related publications are

the Provision for the Application of Safety Standards Series the Radiological Assessment

Reports Series and the International Nuclear Safety Grouprsquos INSAG Series The IAEA also issues

reports on radiological accidents and other special publications

Safety related publications are also issued in the Technical Reports Series the IAEA-

TECDOC Series the Training Course Series and the IAEA Services Series and as

Practical Radiation Safety Manuals and Practical Radiation Technical Manuals Security

related publications are issued in the IAEA Nuclear Security Series

FOREWORD

by Yukiya Amano

Director General

EDITORIAL NOTE

CONTENTS

1 INTRODUCTION 11

BACKGROUND 11

OBJECTIVE 33

SCOPE 33

STRUCTURE 44

2 OVERVIEW OF MONITORING AND SURVEILLANCE 55

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES 66

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY REGARDING

MONITORING AND SURVEILLANCE PROGRAMMES 99

RESPONSIBILITIES OF THE OPERATOR 99

RESPONSIBILITIES OF THE REGULATORY BODY 99

4 DESIGN OF A MONITORING PROGRAMME 1313

5 MONITORING BY TYPE OF DISPOSAL FACILITY 1919

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME 2121

MONITORING FOR EMERGENCY RESPONSE 2424

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE

PROGRAMME 2727

TYPE AND FREQUENCY OF INSPECTIONS 2828

8 USE OF MONITORING AND SURVEILLANCE INFORMATION 3131

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES 3131

DEVIATIONS FROM EXPECTED RESULTS 3333

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE

PROGRAMME 3434

9 MANAGEMENT SYSTEM 3535

ANNEX I 3939

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION

COLLECTED FOR A GEOLOGICAL DISPOSAL PROGRAMME 3939

ANNEX II 5151

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FOR A NEAR SURFACE

DISPOSAL PROGRAMME 5151

1

1 INTRODUCTION

BACKGROUND

11 Radioactive waste arises from the generation of electricity in nuclear power plants from

nuclear fuel cycle operations and from other activities in the nuclear fuel cycle such as mining and

milling of uranium and thorium ores Radioactive waste also arises in a wide range of industrial and

medical activities It also arises from activities and processes in which radioactive materials of natural

origin become concentrated in waste material and safety needs to be considered in its management

12 A monitoring and surveillance programme is an important element in providing reassurance

that a disposal facility for radioactive waste provides the required level of safety during its operational

period and post-closure period depending on the type of the disposal The safety principles to be

applied in all radioactive waste management activities are set out in the IAEA Fundamental Safety

Principles [1] Within the safety standards series the safety requirements for Near Surface Disposal of

Radioactive Waste [2] and Geological Disposal of Radioactive Waste [3] providing specific

monitoring requirements for their respective types of facilities have been combined to create a single

safety standard for Disposal of Radioactive Waste [4]

13 The IAEA is also developing a Safety Guide on geological disposal facilities for radioactive

waste [5] and is preparing a Safety Guide on near surface disposal facilities for radioactive wastes [6]

as well as a Safety Guide on the protection of the public against exposure to natural sources of

radiation including NORM residues [7] The present Safety Guide provides support for these safety

standards in the area of monitoring and surveillance

14 Differing kinds of monitoring activities occur in each period of the lifetime of a radioactive

waste disposal facility This Safety Guide covers monitoring and surveillance during pre-operational

operational and post-closure periods for near surface geological and mine waste disposal facilities

These periods are defined as follows [4]

minus The pre-operational period includes concept definition site evaluation (selection

verification and confirmation) safety assessment and design studies It also includes the

development of those aspects of the safety case for safety in operation and after closure

that are required in order to set the conditions of authorization to obtain the authorization

and to proceed with the construction of the disposal facility and the initial operational

activities The monitoring and testing programmes that are needed to inform operational

management decisions are put in place

minus The operational period begins when waste is first received at the facility From this time

radiation exposures may occur as a result of waste management activities and these are

subject to control in accordance with the requirements for protection and safety

2

Monitoring surveillance and testing programmes continue to inform operational

management decisions and to provide the basis for decisions concerning the closure of

the facility or parts of it Safety assessments for the period of operation and after closure

and the safety case are updated as necessary to reflect actual experience and increasing

knowledge In the operational period construction activities may take place at the same

time as waste emplacement in and closure of other parts of the facility This period may

include activities for waste retrieval mdash if considered necessary mdash prior to closure

activities following the completion of waste emplacement and the final closure and

sealing of the facility

minus The post-closure period begins at the time when all the engineered containment and

isolation features have been put in place operational buildings and supporting services

have been decommissioned and the facility is in its final configuration After its closure

the safety of the disposal facility is provided for by means of passive features inherent in

the characteristics of the site and the facility and characteristics of the waste packages

together with certain institutional controls particularly for near surface facilities Such

institutional controls are put in place to prevent intrusion into facilities and to confirm

that the disposal system is performing as expected by means of monitoring and

surveillance Monitoring may also be carried out to provide public assurance The licence

will be terminated after the period of active institutional control when all the necessary

technical legal and financial requirements have been fulfilled

15 The International Basic Safety Standards for Protection against Ionizing Radiation and for the

Safety of Radiation Sources (the BSS) [8] and the IAEA Safety Guide for environmental and source

monitoring for purposes of radiation protection Ref [9] provide a framework for all generic aspects of

radiological monitoring In particular Ref [8] establishes the basic requirements for radiological

monitoring of public exposure and Ref [9] covers pre-operational monitoring operational monitoring

(including decommissioning) and post-closure radiological monitoring It also acknowledges the need

for monitoring a variety of non-radiological variables The present Safety Guide is intended to

elaborate upon the requirements in the BSS and to complement the guidance provided in Ref [9] in

particular in regard to performance monitoring aspects of disposal facility development On matters

pertaining to source and environmental monitoring the present Safety Guide is subsidiary to and

defers to Ref [9]

16 The draft International Basic Safety Standards currently under development to supersede Ref

[8] will contain an updated and extended set of requirements on the regulatory control and monitoring

of public exposure and safety of the radioactive waste management

17 There are presently four IAEA publications concerned with monitoring and surveillance of

disposal facilities Safety Reports Series No 27 on Monitoring and Surveillance of Residues from the

3

Mining and Milling of Uranium and Thorium [10] Safety Reports Series No 35 on Surveillance and

Monitoring of Near Surface Disposal Facilities for Radioactive Waste [11] Safety Reports Series No

64 on Programmes and Systems for Source and Environmental Radiation Monitoring [18] and IAEA-

TECDOC-1208 on Monitoring of Geological Repositories for High Level Radioactive Waste [12]

These publications have served as resources for development of the present Safety Guide

OBJECTIVE

18 The objective of this Safety Guide is to provide guidance for monitoring and surveillance of

radioactive waste disposal facilities during their entire lifetime The Safety Guide includes the

different objectives that monitoring has at the lifetime periods from initiation of work on a candidate

site to the period after closure of the disposal facility

SCOPE

19 This Safety Guide considers the monitoring and surveillance of three types of disposal

facilities

bull Near surface disposal facilities

bull Geological disposal facilities

bull Disposal facilities for uranium and thorium mine waste

The three types of disposal facilities listed above are considered to cover all the disposal options as

identified in the Safety Requirements on Disposal of Radioactive Waste [4] In this Safety Guide

borehole disposal facilities are not specifically addressed However borehole disposal is not

conceptually different from either near surface disposal or geological disposal of radioactive waste A

possible surveillance and monitoring programme suitable for a small scale borehole disposal facility is

discussed in other IAEA Safety Standards [20]

110 As explained in Ref [14] the term near surface disposal refers generally to disposal at or

within a few tens of metres of the ground surface The term geological disposal generally refers to

disposal in deep stable geological formations usually several hundred meters or more below the

surface Mining waste disposal facilities cover a spectrum of designs from above-grade mounds to

geological disposal of tailings slimes sometimes used as backfill in old mine workings The type of

disposal is controlled by the waste characteristics and in any case the suitability of waste for disposal

in a particular disposal facility is required to be demonstrated by the safety case and supporting safety

assessment for the facility From the safety point of view disposal depth is one of the factors

considered in assessing the safety of disposal the geological environment the waste characteristics

4

and engineered features are of equal or more importance than depth of disposal in assessing the safety

of disposal facility

111 This Safety Guide places emphasis on an approach to monitoring and surveillance that

provides data needed for the development of the safety case The safety case includes information

needed for siting construct operate and close the facility for supporting decisions on managing the

disposal programme as well as information that are of particular interest to interested parties [4]

Technical details on monitoring and surveillance methodologies are beyond the scope of this Safety

Guide however Refs [10 11 12 18] direct the reader to such information and Annexes I and II give

examples of monitoring programmes for geological and near surface disposal programmes

112 This Safety Guide does not specifically address monitoring that will be required for

bull Operating personnel

bull Waste characterization or tracking

bull Nuclear materials control in the case of facilities that will contain significant quantities of

nuclear materials

Nor does it focus on monitoring for non-radiological contaminants that may be of potential concern

Facility operators however should consider such contaminants when designing their monitoring

programme

113 This Safety Guide does not address monitoring for occupational exposure rather the focus is

on monitoring for disposal system performance and radiation protection of the public and the

environment Monitoring for occupational radiation protection is discussed in other IAEA safety

standards [13]

STRUCTURE

114 Section 2 provides an overview of monitoring and surveillance for radioactive waste disposal

facilities and describes overall objectives for a monitoring and surveillance programme Section 3

addresses roles and responsibilities of the regulatory body and the implementing organizations with

regard to monitoring and surveillance Sections 4 5 and 6 focus on monitoring More specifically

Section 4 addresses design of a monitoring programme and includes some consideration of strategic

issues for monitoring Section 5 provides guidance on monitoring according to the type of disposal

facility (geological near surface and facilities for mining and milling waste) Section 6 addresses

monitoring according to the stage of facility development Section 7 provides specific guidance for

surveillance activities only Finally Section 8 is concerned with the use of monitoring and surveillance

information in regard to compliance aspects and development and improvement of the safety case and

Section 9 provides a brief discussion of the salient issues pertaining to the management system for a

disposal facility

5

2 OVERVIEW OF MONITORING AND SURVEILLANCE

21 The BSS [8] defines lsquomonitoringrsquo (of public exposure) to be

ldquoThe measurement of dose or contamination for reasons related to the assessment or

control of exposure to radiation or radioactive substances and the interpretation of the

resultsrdquo

22 The IAEA Safety Guide on environmental and source monitoring [9] defines the terms lsquosource

monitoringrsquo and lsquoenvironmental monitoringrsquo as

a ldquoSource monitoring The measurement of activity in radioactive materials being

released to the environment or of external dose rates due to sources within a facility or

activityrdquo

b ldquoEnvironmental monitoring The measurement of external dose rates due to sources in

the environment or of radionuclide concentrations in environmental mediardquo

23 In the context of this Safety Guide the term monitoring refers to

Continuous or periodic observations and measurements of environmental engineering or

radiological parameters to help evaluate the behaviour of components of the waste

disposal system or of the impacts of the waste disposal system and its operation on the

public and the environment

24 Monitoring involves many characterization activities Information may have to be collected

over a period of time for a number of characterization tasks (eg groundwater flow rates moisture

content of soils daily precipitation) For other types of information once the parameter has been

defined there may be no need to continue with the sampling and measurement since it is not expected

to change in time or with development and closure of the facility (eg rock porosity)

25 Monitoring is needed to evaluate processes or parameters that are influential in the

development of the safety case The duration and frequency of monitoring may be determined by

regulatory requirements by the time scale of natural variations in a process or parameter by possible

changes associated with the construction and operation of the facility The need to address public

concern should also be considered in defining the monitoring programme

26 A programme for the surveillance of the facility should be established and implemented as

necessary and feasible It should consist of planned activities carried out to verify that the facility is

operating within the design limits and conditions and to detect any deterioration of structures systems

and components that could result in unsafe conditions [17] In the context of this Safety Guide the

term surveillance refers to

6

The physical inspection of a waste management facility in order to verify its integrity to

protect and preserve the passive safety barriers

27 Some countries do not differentiate between monitoring and surveillance of disposal facilities

28 In this respect the function of surveillance is to contribute to the detection of changes in the

engineering structures and systems of the disposal facility which might affect the radiological

performance of the system The relevant and expected changes can be identified by the post closure

safety assessment The surveillance programme is usually implemented through regular inspections of

the critical components of the waste disposal facility

29 Generally there is a need to collect site-specific data although some relevant monitoring data

may be available from other sources Safety cases are usually supported by data from a number of

sources which includes site-specific measurements regional data and generic information

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES

210 Requirement 21 of the Safety Requirements on the Disposal of Radioactive Waste [4] states

that ldquoA programme of monitoring shall be carried out prior to and during the construction and

operation of a disposal facility and after its closure if this is part of the safety case This programme

shall be designed to collect and update information necessary for the purposes of protection and safety

Information shall be obtained to confirm the conditions necessary for the safety of workers and

members of the public and protection of the environment during the period of operation of the facility

Monitoring shall also be carried out to confirm the absence of any conditions that could affect the

safety of the facility after closurerdquo

211 In addition Requirement 10 of Ref [4] indicates that ldquoAn appropriate level of surveillance and

control shall be applied to protect and preserve the passive safety features to the extent that this is

necessary so that they can fulfil the functions that they are assigned in the safety case for safety after

closurerdquo

212 Monitoring and surveillance programmes begin at site characterization phase of disposal

facility development and continue to evolve through to the post-closure period depending on the type

of the disposal facility The data collected and insights derived from monitoring should be integrated

into and inform planning decisions made throughout the life-cycle of a disposal facility As a result

provision should be made to anticipate the needs of monitoring at later periods of the facility lifetime

and to gather monitoring data that informs later planning and actions

213 Monitoring and surveillance of disposal facilities for radioactive waste has four broad

objectives

7

1 To demonstrate compliance with the regulatory constraints and licence conditions

2 To verify that the disposal system is functioning as expected This means that the components

fulfil their function as identified in the safety case and that actual conditions are consistent

with the assumptions made for post-closure safety

3 To strengthen understanding of aspects of system behaviour used in developing the safety case

for the dispoal facility and to allow further testing of models predicting those aspects

4 To accumulate an environmental database of the site the disposal facility and its surroundings

for future decisions that are part of a stepwise programme of construction operation and

closure of the disposal facility

214 As mentioned in Ref [4] ldquoMonitoring programmes are designed and implemented so as not to

reduce the overall level of safety of the facility after closurerdquo (para 54) ldquoTo some extent the safety of

a disposal facility can depend on some future actions such as maintenance work or surveillance

However this dependence has to be minimized to the extent possiblerdquo (para 322) ldquoFor a geological

disposal facility it is possible to provide for safety after closure by means of passive features In the

case of a near surface disposal facility actions such as maintenance monitoring or surveillance may

be necessary for a period of time after closure to ensure safetyrdquo (para 323)

215 The monitoring programme should be closely tied to the safety case Even if safety should not

rely on monitoring and surveillance the results of such a programme should be used to strengthen the

safety case and build confidence in safety As well information needs of the safety case should be

used to improve the monitoring program

216 Requirement 7 of Ref [4] indicates that ldquoThe host environment shall be selected the

engineered barriers of the disposal facility shall be designed and the facility shall be operated to ensure

that safety is provided by means of multiple safety functions Containment and isolation of the waste

shall be provided by means of a number of physical barriers of the disposal systemrdquo The monitoring

and surveillance programme should provide to the extent practical the necessary information to

ensure that each barrier and its associated safety function(s) performs as planned and indicated in the

safety case In addition the monitoring and surveillance programme should confirm that the

performances of the engineered and natural barriers are not damaged by the operational activities

217 Further to its technical objectives a monitoring and surveillance programme can be a suitable

tool for public reassurance In that sense consideration of public interest and interested parties

concerns may provide useful information to improve the monitoring programme by including social

aspects

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 3: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

DS357

2011-03-15

IAEA SAFETY STANDARDS for protecting people and the environment

Monitoring and Surveillance of Radioactive Waste Disposal Facilities DRAFT SAFETY GUIDE

DS357

Draft Safety Guide

Action For submission to Member States for comment (Step 8)

IAEA SAFETY RELATED PUBLICATIONS

IAEA SAFETY STANDARDS

Under the terms of Article III of its Statute the IAEA is authorized to establish or adopt

standards of safety for protection of health and minimization of danger to life and property and to

provide for the application of these standards

The publications by means of which the IAEA establishes standards are issued in the IAEA

Safety Standards Series This series covers nuclear safety radiation safety transport safety and waste

safety and also general safety (ie all these areas of safety) The publication categories in the series

are Safety Fundamentals Safety Requirements and Safety Guides

Safety standards are coded according to their coverage nuclear safety (NS) radiation safety

(RS) transport safety (TS) waste safety (WS) and general safety (GS)

Information on the IAEArsquos safety standards programme is available at the IAEA Internet site

httpwww-nsiaeaorgstandards

The site provides the texts in English of published and draft safety standards The texts of safety

standards issued in Arabic Chinese French Russian and Spanish the IAEA Safety Glossary and a

status report for safety standards under development are also available For further information please

contact the IAEA at PO Box 100 A-1400 Vienna Austria

All users of IAEA safety standards are invited to inform the IAEA of experience in their use (eg

as a basis for national regulations for safety reviews and for training courses) for the purpose of ensuring

that they continue to meet usersrsquo needs Information may be provided via the IAEA Internet site or by

post as above or by e-mail to OfficialMailiaeaorg

OTHER SAFETY RELATED PUBLICATIONS

The IAEA provides for the application of the standards and under the terms of Articles III and

VIIIC of its Statute makes available and fosters the exchange of information relating to peaceful

nuclear activities and serves as an intermediary among its Member States for this purpose

Reports on safety and protection in nuclear activities are issued in other publications series in

particular the Safety Reports Series Safety Reports provide practical examples and detailed methods

that can be used in support of the safety standards Other IAEA series of safety related publications are

the Provision for the Application of Safety Standards Series the Radiological Assessment

Reports Series and the International Nuclear Safety Grouprsquos INSAG Series The IAEA also issues

reports on radiological accidents and other special publications

Safety related publications are also issued in the Technical Reports Series the IAEA-

TECDOC Series the Training Course Series and the IAEA Services Series and as

Practical Radiation Safety Manuals and Practical Radiation Technical Manuals Security

related publications are issued in the IAEA Nuclear Security Series

FOREWORD

by Yukiya Amano

Director General

EDITORIAL NOTE

CONTENTS

1 INTRODUCTION 11

BACKGROUND 11

OBJECTIVE 33

SCOPE 33

STRUCTURE 44

2 OVERVIEW OF MONITORING AND SURVEILLANCE 55

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES 66

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY REGARDING

MONITORING AND SURVEILLANCE PROGRAMMES 99

RESPONSIBILITIES OF THE OPERATOR 99

RESPONSIBILITIES OF THE REGULATORY BODY 99

4 DESIGN OF A MONITORING PROGRAMME 1313

5 MONITORING BY TYPE OF DISPOSAL FACILITY 1919

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME 2121

MONITORING FOR EMERGENCY RESPONSE 2424

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE

PROGRAMME 2727

TYPE AND FREQUENCY OF INSPECTIONS 2828

8 USE OF MONITORING AND SURVEILLANCE INFORMATION 3131

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES 3131

DEVIATIONS FROM EXPECTED RESULTS 3333

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE

PROGRAMME 3434

9 MANAGEMENT SYSTEM 3535

ANNEX I 3939

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION

COLLECTED FOR A GEOLOGICAL DISPOSAL PROGRAMME 3939

ANNEX II 5151

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FOR A NEAR SURFACE

DISPOSAL PROGRAMME 5151

1

1 INTRODUCTION

BACKGROUND

11 Radioactive waste arises from the generation of electricity in nuclear power plants from

nuclear fuel cycle operations and from other activities in the nuclear fuel cycle such as mining and

milling of uranium and thorium ores Radioactive waste also arises in a wide range of industrial and

medical activities It also arises from activities and processes in which radioactive materials of natural

origin become concentrated in waste material and safety needs to be considered in its management

12 A monitoring and surveillance programme is an important element in providing reassurance

that a disposal facility for radioactive waste provides the required level of safety during its operational

period and post-closure period depending on the type of the disposal The safety principles to be

applied in all radioactive waste management activities are set out in the IAEA Fundamental Safety

Principles [1] Within the safety standards series the safety requirements for Near Surface Disposal of

Radioactive Waste [2] and Geological Disposal of Radioactive Waste [3] providing specific

monitoring requirements for their respective types of facilities have been combined to create a single

safety standard for Disposal of Radioactive Waste [4]

13 The IAEA is also developing a Safety Guide on geological disposal facilities for radioactive

waste [5] and is preparing a Safety Guide on near surface disposal facilities for radioactive wastes [6]

as well as a Safety Guide on the protection of the public against exposure to natural sources of

radiation including NORM residues [7] The present Safety Guide provides support for these safety

standards in the area of monitoring and surveillance

14 Differing kinds of monitoring activities occur in each period of the lifetime of a radioactive

waste disposal facility This Safety Guide covers monitoring and surveillance during pre-operational

operational and post-closure periods for near surface geological and mine waste disposal facilities

These periods are defined as follows [4]

minus The pre-operational period includes concept definition site evaluation (selection

verification and confirmation) safety assessment and design studies It also includes the

development of those aspects of the safety case for safety in operation and after closure

that are required in order to set the conditions of authorization to obtain the authorization

and to proceed with the construction of the disposal facility and the initial operational

activities The monitoring and testing programmes that are needed to inform operational

management decisions are put in place

minus The operational period begins when waste is first received at the facility From this time

radiation exposures may occur as a result of waste management activities and these are

subject to control in accordance with the requirements for protection and safety

2

Monitoring surveillance and testing programmes continue to inform operational

management decisions and to provide the basis for decisions concerning the closure of

the facility or parts of it Safety assessments for the period of operation and after closure

and the safety case are updated as necessary to reflect actual experience and increasing

knowledge In the operational period construction activities may take place at the same

time as waste emplacement in and closure of other parts of the facility This period may

include activities for waste retrieval mdash if considered necessary mdash prior to closure

activities following the completion of waste emplacement and the final closure and

sealing of the facility

minus The post-closure period begins at the time when all the engineered containment and

isolation features have been put in place operational buildings and supporting services

have been decommissioned and the facility is in its final configuration After its closure

the safety of the disposal facility is provided for by means of passive features inherent in

the characteristics of the site and the facility and characteristics of the waste packages

together with certain institutional controls particularly for near surface facilities Such

institutional controls are put in place to prevent intrusion into facilities and to confirm

that the disposal system is performing as expected by means of monitoring and

surveillance Monitoring may also be carried out to provide public assurance The licence

will be terminated after the period of active institutional control when all the necessary

technical legal and financial requirements have been fulfilled

15 The International Basic Safety Standards for Protection against Ionizing Radiation and for the

Safety of Radiation Sources (the BSS) [8] and the IAEA Safety Guide for environmental and source

monitoring for purposes of radiation protection Ref [9] provide a framework for all generic aspects of

radiological monitoring In particular Ref [8] establishes the basic requirements for radiological

monitoring of public exposure and Ref [9] covers pre-operational monitoring operational monitoring

(including decommissioning) and post-closure radiological monitoring It also acknowledges the need

for monitoring a variety of non-radiological variables The present Safety Guide is intended to

elaborate upon the requirements in the BSS and to complement the guidance provided in Ref [9] in

particular in regard to performance monitoring aspects of disposal facility development On matters

pertaining to source and environmental monitoring the present Safety Guide is subsidiary to and

defers to Ref [9]

16 The draft International Basic Safety Standards currently under development to supersede Ref

[8] will contain an updated and extended set of requirements on the regulatory control and monitoring

of public exposure and safety of the radioactive waste management

17 There are presently four IAEA publications concerned with monitoring and surveillance of

disposal facilities Safety Reports Series No 27 on Monitoring and Surveillance of Residues from the

3

Mining and Milling of Uranium and Thorium [10] Safety Reports Series No 35 on Surveillance and

Monitoring of Near Surface Disposal Facilities for Radioactive Waste [11] Safety Reports Series No

64 on Programmes and Systems for Source and Environmental Radiation Monitoring [18] and IAEA-

TECDOC-1208 on Monitoring of Geological Repositories for High Level Radioactive Waste [12]

These publications have served as resources for development of the present Safety Guide

OBJECTIVE

18 The objective of this Safety Guide is to provide guidance for monitoring and surveillance of

radioactive waste disposal facilities during their entire lifetime The Safety Guide includes the

different objectives that monitoring has at the lifetime periods from initiation of work on a candidate

site to the period after closure of the disposal facility

SCOPE

19 This Safety Guide considers the monitoring and surveillance of three types of disposal

facilities

bull Near surface disposal facilities

bull Geological disposal facilities

bull Disposal facilities for uranium and thorium mine waste

The three types of disposal facilities listed above are considered to cover all the disposal options as

identified in the Safety Requirements on Disposal of Radioactive Waste [4] In this Safety Guide

borehole disposal facilities are not specifically addressed However borehole disposal is not

conceptually different from either near surface disposal or geological disposal of radioactive waste A

possible surveillance and monitoring programme suitable for a small scale borehole disposal facility is

discussed in other IAEA Safety Standards [20]

110 As explained in Ref [14] the term near surface disposal refers generally to disposal at or

within a few tens of metres of the ground surface The term geological disposal generally refers to

disposal in deep stable geological formations usually several hundred meters or more below the

surface Mining waste disposal facilities cover a spectrum of designs from above-grade mounds to

geological disposal of tailings slimes sometimes used as backfill in old mine workings The type of

disposal is controlled by the waste characteristics and in any case the suitability of waste for disposal

in a particular disposal facility is required to be demonstrated by the safety case and supporting safety

assessment for the facility From the safety point of view disposal depth is one of the factors

considered in assessing the safety of disposal the geological environment the waste characteristics

4

and engineered features are of equal or more importance than depth of disposal in assessing the safety

of disposal facility

111 This Safety Guide places emphasis on an approach to monitoring and surveillance that

provides data needed for the development of the safety case The safety case includes information

needed for siting construct operate and close the facility for supporting decisions on managing the

disposal programme as well as information that are of particular interest to interested parties [4]

Technical details on monitoring and surveillance methodologies are beyond the scope of this Safety

Guide however Refs [10 11 12 18] direct the reader to such information and Annexes I and II give

examples of monitoring programmes for geological and near surface disposal programmes

112 This Safety Guide does not specifically address monitoring that will be required for

bull Operating personnel

bull Waste characterization or tracking

bull Nuclear materials control in the case of facilities that will contain significant quantities of

nuclear materials

Nor does it focus on monitoring for non-radiological contaminants that may be of potential concern

Facility operators however should consider such contaminants when designing their monitoring

programme

113 This Safety Guide does not address monitoring for occupational exposure rather the focus is

on monitoring for disposal system performance and radiation protection of the public and the

environment Monitoring for occupational radiation protection is discussed in other IAEA safety

standards [13]

STRUCTURE

114 Section 2 provides an overview of monitoring and surveillance for radioactive waste disposal

facilities and describes overall objectives for a monitoring and surveillance programme Section 3

addresses roles and responsibilities of the regulatory body and the implementing organizations with

regard to monitoring and surveillance Sections 4 5 and 6 focus on monitoring More specifically

Section 4 addresses design of a monitoring programme and includes some consideration of strategic

issues for monitoring Section 5 provides guidance on monitoring according to the type of disposal

facility (geological near surface and facilities for mining and milling waste) Section 6 addresses

monitoring according to the stage of facility development Section 7 provides specific guidance for

surveillance activities only Finally Section 8 is concerned with the use of monitoring and surveillance

information in regard to compliance aspects and development and improvement of the safety case and

Section 9 provides a brief discussion of the salient issues pertaining to the management system for a

disposal facility

5

2 OVERVIEW OF MONITORING AND SURVEILLANCE

21 The BSS [8] defines lsquomonitoringrsquo (of public exposure) to be

ldquoThe measurement of dose or contamination for reasons related to the assessment or

control of exposure to radiation or radioactive substances and the interpretation of the

resultsrdquo

22 The IAEA Safety Guide on environmental and source monitoring [9] defines the terms lsquosource

monitoringrsquo and lsquoenvironmental monitoringrsquo as

a ldquoSource monitoring The measurement of activity in radioactive materials being

released to the environment or of external dose rates due to sources within a facility or

activityrdquo

b ldquoEnvironmental monitoring The measurement of external dose rates due to sources in

the environment or of radionuclide concentrations in environmental mediardquo

23 In the context of this Safety Guide the term monitoring refers to

Continuous or periodic observations and measurements of environmental engineering or

radiological parameters to help evaluate the behaviour of components of the waste

disposal system or of the impacts of the waste disposal system and its operation on the

public and the environment

24 Monitoring involves many characterization activities Information may have to be collected

over a period of time for a number of characterization tasks (eg groundwater flow rates moisture

content of soils daily precipitation) For other types of information once the parameter has been

defined there may be no need to continue with the sampling and measurement since it is not expected

to change in time or with development and closure of the facility (eg rock porosity)

25 Monitoring is needed to evaluate processes or parameters that are influential in the

development of the safety case The duration and frequency of monitoring may be determined by

regulatory requirements by the time scale of natural variations in a process or parameter by possible

changes associated with the construction and operation of the facility The need to address public

concern should also be considered in defining the monitoring programme

26 A programme for the surveillance of the facility should be established and implemented as

necessary and feasible It should consist of planned activities carried out to verify that the facility is

operating within the design limits and conditions and to detect any deterioration of structures systems

and components that could result in unsafe conditions [17] In the context of this Safety Guide the

term surveillance refers to

6

The physical inspection of a waste management facility in order to verify its integrity to

protect and preserve the passive safety barriers

27 Some countries do not differentiate between monitoring and surveillance of disposal facilities

28 In this respect the function of surveillance is to contribute to the detection of changes in the

engineering structures and systems of the disposal facility which might affect the radiological

performance of the system The relevant and expected changes can be identified by the post closure

safety assessment The surveillance programme is usually implemented through regular inspections of

the critical components of the waste disposal facility

29 Generally there is a need to collect site-specific data although some relevant monitoring data

may be available from other sources Safety cases are usually supported by data from a number of

sources which includes site-specific measurements regional data and generic information

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES

210 Requirement 21 of the Safety Requirements on the Disposal of Radioactive Waste [4] states

that ldquoA programme of monitoring shall be carried out prior to and during the construction and

operation of a disposal facility and after its closure if this is part of the safety case This programme

shall be designed to collect and update information necessary for the purposes of protection and safety

Information shall be obtained to confirm the conditions necessary for the safety of workers and

members of the public and protection of the environment during the period of operation of the facility

Monitoring shall also be carried out to confirm the absence of any conditions that could affect the

safety of the facility after closurerdquo

211 In addition Requirement 10 of Ref [4] indicates that ldquoAn appropriate level of surveillance and

control shall be applied to protect and preserve the passive safety features to the extent that this is

necessary so that they can fulfil the functions that they are assigned in the safety case for safety after

closurerdquo

212 Monitoring and surveillance programmes begin at site characterization phase of disposal

facility development and continue to evolve through to the post-closure period depending on the type

of the disposal facility The data collected and insights derived from monitoring should be integrated

into and inform planning decisions made throughout the life-cycle of a disposal facility As a result

provision should be made to anticipate the needs of monitoring at later periods of the facility lifetime

and to gather monitoring data that informs later planning and actions

213 Monitoring and surveillance of disposal facilities for radioactive waste has four broad

objectives

7

1 To demonstrate compliance with the regulatory constraints and licence conditions

2 To verify that the disposal system is functioning as expected This means that the components

fulfil their function as identified in the safety case and that actual conditions are consistent

with the assumptions made for post-closure safety

3 To strengthen understanding of aspects of system behaviour used in developing the safety case

for the dispoal facility and to allow further testing of models predicting those aspects

4 To accumulate an environmental database of the site the disposal facility and its surroundings

for future decisions that are part of a stepwise programme of construction operation and

closure of the disposal facility

214 As mentioned in Ref [4] ldquoMonitoring programmes are designed and implemented so as not to

reduce the overall level of safety of the facility after closurerdquo (para 54) ldquoTo some extent the safety of

a disposal facility can depend on some future actions such as maintenance work or surveillance

However this dependence has to be minimized to the extent possiblerdquo (para 322) ldquoFor a geological

disposal facility it is possible to provide for safety after closure by means of passive features In the

case of a near surface disposal facility actions such as maintenance monitoring or surveillance may

be necessary for a period of time after closure to ensure safetyrdquo (para 323)

215 The monitoring programme should be closely tied to the safety case Even if safety should not

rely on monitoring and surveillance the results of such a programme should be used to strengthen the

safety case and build confidence in safety As well information needs of the safety case should be

used to improve the monitoring program

216 Requirement 7 of Ref [4] indicates that ldquoThe host environment shall be selected the

engineered barriers of the disposal facility shall be designed and the facility shall be operated to ensure

that safety is provided by means of multiple safety functions Containment and isolation of the waste

shall be provided by means of a number of physical barriers of the disposal systemrdquo The monitoring

and surveillance programme should provide to the extent practical the necessary information to

ensure that each barrier and its associated safety function(s) performs as planned and indicated in the

safety case In addition the monitoring and surveillance programme should confirm that the

performances of the engineered and natural barriers are not damaged by the operational activities

217 Further to its technical objectives a monitoring and surveillance programme can be a suitable

tool for public reassurance In that sense consideration of public interest and interested parties

concerns may provide useful information to improve the monitoring programme by including social

aspects

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 4: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

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status report for safety standards under development are also available For further information please

contact the IAEA at PO Box 100 A-1400 Vienna Austria

All users of IAEA safety standards are invited to inform the IAEA of experience in their use (eg

as a basis for national regulations for safety reviews and for training courses) for the purpose of ensuring

that they continue to meet usersrsquo needs Information may be provided via the IAEA Internet site or by

post as above or by e-mail to OfficialMailiaeaorg

OTHER SAFETY RELATED PUBLICATIONS

The IAEA provides for the application of the standards and under the terms of Articles III and

VIIIC of its Statute makes available and fosters the exchange of information relating to peaceful

nuclear activities and serves as an intermediary among its Member States for this purpose

Reports on safety and protection in nuclear activities are issued in other publications series in

particular the Safety Reports Series Safety Reports provide practical examples and detailed methods

that can be used in support of the safety standards Other IAEA series of safety related publications are

the Provision for the Application of Safety Standards Series the Radiological Assessment

Reports Series and the International Nuclear Safety Grouprsquos INSAG Series The IAEA also issues

reports on radiological accidents and other special publications

Safety related publications are also issued in the Technical Reports Series the IAEA-

TECDOC Series the Training Course Series and the IAEA Services Series and as

Practical Radiation Safety Manuals and Practical Radiation Technical Manuals Security

related publications are issued in the IAEA Nuclear Security Series

FOREWORD

by Yukiya Amano

Director General

EDITORIAL NOTE

CONTENTS

1 INTRODUCTION 11

BACKGROUND 11

OBJECTIVE 33

SCOPE 33

STRUCTURE 44

2 OVERVIEW OF MONITORING AND SURVEILLANCE 55

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES 66

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY REGARDING

MONITORING AND SURVEILLANCE PROGRAMMES 99

RESPONSIBILITIES OF THE OPERATOR 99

RESPONSIBILITIES OF THE REGULATORY BODY 99

4 DESIGN OF A MONITORING PROGRAMME 1313

5 MONITORING BY TYPE OF DISPOSAL FACILITY 1919

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME 2121

MONITORING FOR EMERGENCY RESPONSE 2424

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE

PROGRAMME 2727

TYPE AND FREQUENCY OF INSPECTIONS 2828

8 USE OF MONITORING AND SURVEILLANCE INFORMATION 3131

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES 3131

DEVIATIONS FROM EXPECTED RESULTS 3333

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE

PROGRAMME 3434

9 MANAGEMENT SYSTEM 3535

ANNEX I 3939

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION

COLLECTED FOR A GEOLOGICAL DISPOSAL PROGRAMME 3939

ANNEX II 5151

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FOR A NEAR SURFACE

DISPOSAL PROGRAMME 5151

1

1 INTRODUCTION

BACKGROUND

11 Radioactive waste arises from the generation of electricity in nuclear power plants from

nuclear fuel cycle operations and from other activities in the nuclear fuel cycle such as mining and

milling of uranium and thorium ores Radioactive waste also arises in a wide range of industrial and

medical activities It also arises from activities and processes in which radioactive materials of natural

origin become concentrated in waste material and safety needs to be considered in its management

12 A monitoring and surveillance programme is an important element in providing reassurance

that a disposal facility for radioactive waste provides the required level of safety during its operational

period and post-closure period depending on the type of the disposal The safety principles to be

applied in all radioactive waste management activities are set out in the IAEA Fundamental Safety

Principles [1] Within the safety standards series the safety requirements for Near Surface Disposal of

Radioactive Waste [2] and Geological Disposal of Radioactive Waste [3] providing specific

monitoring requirements for their respective types of facilities have been combined to create a single

safety standard for Disposal of Radioactive Waste [4]

13 The IAEA is also developing a Safety Guide on geological disposal facilities for radioactive

waste [5] and is preparing a Safety Guide on near surface disposal facilities for radioactive wastes [6]

as well as a Safety Guide on the protection of the public against exposure to natural sources of

radiation including NORM residues [7] The present Safety Guide provides support for these safety

standards in the area of monitoring and surveillance

14 Differing kinds of monitoring activities occur in each period of the lifetime of a radioactive

waste disposal facility This Safety Guide covers monitoring and surveillance during pre-operational

operational and post-closure periods for near surface geological and mine waste disposal facilities

These periods are defined as follows [4]

minus The pre-operational period includes concept definition site evaluation (selection

verification and confirmation) safety assessment and design studies It also includes the

development of those aspects of the safety case for safety in operation and after closure

that are required in order to set the conditions of authorization to obtain the authorization

and to proceed with the construction of the disposal facility and the initial operational

activities The monitoring and testing programmes that are needed to inform operational

management decisions are put in place

minus The operational period begins when waste is first received at the facility From this time

radiation exposures may occur as a result of waste management activities and these are

subject to control in accordance with the requirements for protection and safety

2

Monitoring surveillance and testing programmes continue to inform operational

management decisions and to provide the basis for decisions concerning the closure of

the facility or parts of it Safety assessments for the period of operation and after closure

and the safety case are updated as necessary to reflect actual experience and increasing

knowledge In the operational period construction activities may take place at the same

time as waste emplacement in and closure of other parts of the facility This period may

include activities for waste retrieval mdash if considered necessary mdash prior to closure

activities following the completion of waste emplacement and the final closure and

sealing of the facility

minus The post-closure period begins at the time when all the engineered containment and

isolation features have been put in place operational buildings and supporting services

have been decommissioned and the facility is in its final configuration After its closure

the safety of the disposal facility is provided for by means of passive features inherent in

the characteristics of the site and the facility and characteristics of the waste packages

together with certain institutional controls particularly for near surface facilities Such

institutional controls are put in place to prevent intrusion into facilities and to confirm

that the disposal system is performing as expected by means of monitoring and

surveillance Monitoring may also be carried out to provide public assurance The licence

will be terminated after the period of active institutional control when all the necessary

technical legal and financial requirements have been fulfilled

15 The International Basic Safety Standards for Protection against Ionizing Radiation and for the

Safety of Radiation Sources (the BSS) [8] and the IAEA Safety Guide for environmental and source

monitoring for purposes of radiation protection Ref [9] provide a framework for all generic aspects of

radiological monitoring In particular Ref [8] establishes the basic requirements for radiological

monitoring of public exposure and Ref [9] covers pre-operational monitoring operational monitoring

(including decommissioning) and post-closure radiological monitoring It also acknowledges the need

for monitoring a variety of non-radiological variables The present Safety Guide is intended to

elaborate upon the requirements in the BSS and to complement the guidance provided in Ref [9] in

particular in regard to performance monitoring aspects of disposal facility development On matters

pertaining to source and environmental monitoring the present Safety Guide is subsidiary to and

defers to Ref [9]

16 The draft International Basic Safety Standards currently under development to supersede Ref

[8] will contain an updated and extended set of requirements on the regulatory control and monitoring

of public exposure and safety of the radioactive waste management

17 There are presently four IAEA publications concerned with monitoring and surveillance of

disposal facilities Safety Reports Series No 27 on Monitoring and Surveillance of Residues from the

3

Mining and Milling of Uranium and Thorium [10] Safety Reports Series No 35 on Surveillance and

Monitoring of Near Surface Disposal Facilities for Radioactive Waste [11] Safety Reports Series No

64 on Programmes and Systems for Source and Environmental Radiation Monitoring [18] and IAEA-

TECDOC-1208 on Monitoring of Geological Repositories for High Level Radioactive Waste [12]

These publications have served as resources for development of the present Safety Guide

OBJECTIVE

18 The objective of this Safety Guide is to provide guidance for monitoring and surveillance of

radioactive waste disposal facilities during their entire lifetime The Safety Guide includes the

different objectives that monitoring has at the lifetime periods from initiation of work on a candidate

site to the period after closure of the disposal facility

SCOPE

19 This Safety Guide considers the monitoring and surveillance of three types of disposal

facilities

bull Near surface disposal facilities

bull Geological disposal facilities

bull Disposal facilities for uranium and thorium mine waste

The three types of disposal facilities listed above are considered to cover all the disposal options as

identified in the Safety Requirements on Disposal of Radioactive Waste [4] In this Safety Guide

borehole disposal facilities are not specifically addressed However borehole disposal is not

conceptually different from either near surface disposal or geological disposal of radioactive waste A

possible surveillance and monitoring programme suitable for a small scale borehole disposal facility is

discussed in other IAEA Safety Standards [20]

110 As explained in Ref [14] the term near surface disposal refers generally to disposal at or

within a few tens of metres of the ground surface The term geological disposal generally refers to

disposal in deep stable geological formations usually several hundred meters or more below the

surface Mining waste disposal facilities cover a spectrum of designs from above-grade mounds to

geological disposal of tailings slimes sometimes used as backfill in old mine workings The type of

disposal is controlled by the waste characteristics and in any case the suitability of waste for disposal

in a particular disposal facility is required to be demonstrated by the safety case and supporting safety

assessment for the facility From the safety point of view disposal depth is one of the factors

considered in assessing the safety of disposal the geological environment the waste characteristics

4

and engineered features are of equal or more importance than depth of disposal in assessing the safety

of disposal facility

111 This Safety Guide places emphasis on an approach to monitoring and surveillance that

provides data needed for the development of the safety case The safety case includes information

needed for siting construct operate and close the facility for supporting decisions on managing the

disposal programme as well as information that are of particular interest to interested parties [4]

Technical details on monitoring and surveillance methodologies are beyond the scope of this Safety

Guide however Refs [10 11 12 18] direct the reader to such information and Annexes I and II give

examples of monitoring programmes for geological and near surface disposal programmes

112 This Safety Guide does not specifically address monitoring that will be required for

bull Operating personnel

bull Waste characterization or tracking

bull Nuclear materials control in the case of facilities that will contain significant quantities of

nuclear materials

Nor does it focus on monitoring for non-radiological contaminants that may be of potential concern

Facility operators however should consider such contaminants when designing their monitoring

programme

113 This Safety Guide does not address monitoring for occupational exposure rather the focus is

on monitoring for disposal system performance and radiation protection of the public and the

environment Monitoring for occupational radiation protection is discussed in other IAEA safety

standards [13]

STRUCTURE

114 Section 2 provides an overview of monitoring and surveillance for radioactive waste disposal

facilities and describes overall objectives for a monitoring and surveillance programme Section 3

addresses roles and responsibilities of the regulatory body and the implementing organizations with

regard to monitoring and surveillance Sections 4 5 and 6 focus on monitoring More specifically

Section 4 addresses design of a monitoring programme and includes some consideration of strategic

issues for monitoring Section 5 provides guidance on monitoring according to the type of disposal

facility (geological near surface and facilities for mining and milling waste) Section 6 addresses

monitoring according to the stage of facility development Section 7 provides specific guidance for

surveillance activities only Finally Section 8 is concerned with the use of monitoring and surveillance

information in regard to compliance aspects and development and improvement of the safety case and

Section 9 provides a brief discussion of the salient issues pertaining to the management system for a

disposal facility

5

2 OVERVIEW OF MONITORING AND SURVEILLANCE

21 The BSS [8] defines lsquomonitoringrsquo (of public exposure) to be

ldquoThe measurement of dose or contamination for reasons related to the assessment or

control of exposure to radiation or radioactive substances and the interpretation of the

resultsrdquo

22 The IAEA Safety Guide on environmental and source monitoring [9] defines the terms lsquosource

monitoringrsquo and lsquoenvironmental monitoringrsquo as

a ldquoSource monitoring The measurement of activity in radioactive materials being

released to the environment or of external dose rates due to sources within a facility or

activityrdquo

b ldquoEnvironmental monitoring The measurement of external dose rates due to sources in

the environment or of radionuclide concentrations in environmental mediardquo

23 In the context of this Safety Guide the term monitoring refers to

Continuous or periodic observations and measurements of environmental engineering or

radiological parameters to help evaluate the behaviour of components of the waste

disposal system or of the impacts of the waste disposal system and its operation on the

public and the environment

24 Monitoring involves many characterization activities Information may have to be collected

over a period of time for a number of characterization tasks (eg groundwater flow rates moisture

content of soils daily precipitation) For other types of information once the parameter has been

defined there may be no need to continue with the sampling and measurement since it is not expected

to change in time or with development and closure of the facility (eg rock porosity)

25 Monitoring is needed to evaluate processes or parameters that are influential in the

development of the safety case The duration and frequency of monitoring may be determined by

regulatory requirements by the time scale of natural variations in a process or parameter by possible

changes associated with the construction and operation of the facility The need to address public

concern should also be considered in defining the monitoring programme

26 A programme for the surveillance of the facility should be established and implemented as

necessary and feasible It should consist of planned activities carried out to verify that the facility is

operating within the design limits and conditions and to detect any deterioration of structures systems

and components that could result in unsafe conditions [17] In the context of this Safety Guide the

term surveillance refers to

6

The physical inspection of a waste management facility in order to verify its integrity to

protect and preserve the passive safety barriers

27 Some countries do not differentiate between monitoring and surveillance of disposal facilities

28 In this respect the function of surveillance is to contribute to the detection of changes in the

engineering structures and systems of the disposal facility which might affect the radiological

performance of the system The relevant and expected changes can be identified by the post closure

safety assessment The surveillance programme is usually implemented through regular inspections of

the critical components of the waste disposal facility

29 Generally there is a need to collect site-specific data although some relevant monitoring data

may be available from other sources Safety cases are usually supported by data from a number of

sources which includes site-specific measurements regional data and generic information

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES

210 Requirement 21 of the Safety Requirements on the Disposal of Radioactive Waste [4] states

that ldquoA programme of monitoring shall be carried out prior to and during the construction and

operation of a disposal facility and after its closure if this is part of the safety case This programme

shall be designed to collect and update information necessary for the purposes of protection and safety

Information shall be obtained to confirm the conditions necessary for the safety of workers and

members of the public and protection of the environment during the period of operation of the facility

Monitoring shall also be carried out to confirm the absence of any conditions that could affect the

safety of the facility after closurerdquo

211 In addition Requirement 10 of Ref [4] indicates that ldquoAn appropriate level of surveillance and

control shall be applied to protect and preserve the passive safety features to the extent that this is

necessary so that they can fulfil the functions that they are assigned in the safety case for safety after

closurerdquo

212 Monitoring and surveillance programmes begin at site characterization phase of disposal

facility development and continue to evolve through to the post-closure period depending on the type

of the disposal facility The data collected and insights derived from monitoring should be integrated

into and inform planning decisions made throughout the life-cycle of a disposal facility As a result

provision should be made to anticipate the needs of monitoring at later periods of the facility lifetime

and to gather monitoring data that informs later planning and actions

213 Monitoring and surveillance of disposal facilities for radioactive waste has four broad

objectives

7

1 To demonstrate compliance with the regulatory constraints and licence conditions

2 To verify that the disposal system is functioning as expected This means that the components

fulfil their function as identified in the safety case and that actual conditions are consistent

with the assumptions made for post-closure safety

3 To strengthen understanding of aspects of system behaviour used in developing the safety case

for the dispoal facility and to allow further testing of models predicting those aspects

4 To accumulate an environmental database of the site the disposal facility and its surroundings

for future decisions that are part of a stepwise programme of construction operation and

closure of the disposal facility

214 As mentioned in Ref [4] ldquoMonitoring programmes are designed and implemented so as not to

reduce the overall level of safety of the facility after closurerdquo (para 54) ldquoTo some extent the safety of

a disposal facility can depend on some future actions such as maintenance work or surveillance

However this dependence has to be minimized to the extent possiblerdquo (para 322) ldquoFor a geological

disposal facility it is possible to provide for safety after closure by means of passive features In the

case of a near surface disposal facility actions such as maintenance monitoring or surveillance may

be necessary for a period of time after closure to ensure safetyrdquo (para 323)

215 The monitoring programme should be closely tied to the safety case Even if safety should not

rely on monitoring and surveillance the results of such a programme should be used to strengthen the

safety case and build confidence in safety As well information needs of the safety case should be

used to improve the monitoring program

216 Requirement 7 of Ref [4] indicates that ldquoThe host environment shall be selected the

engineered barriers of the disposal facility shall be designed and the facility shall be operated to ensure

that safety is provided by means of multiple safety functions Containment and isolation of the waste

shall be provided by means of a number of physical barriers of the disposal systemrdquo The monitoring

and surveillance programme should provide to the extent practical the necessary information to

ensure that each barrier and its associated safety function(s) performs as planned and indicated in the

safety case In addition the monitoring and surveillance programme should confirm that the

performances of the engineered and natural barriers are not damaged by the operational activities

217 Further to its technical objectives a monitoring and surveillance programme can be a suitable

tool for public reassurance In that sense consideration of public interest and interested parties

concerns may provide useful information to improve the monitoring programme by including social

aspects

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 5: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

Reports Series and the International Nuclear Safety Grouprsquos INSAG Series The IAEA also issues

reports on radiological accidents and other special publications

Safety related publications are also issued in the Technical Reports Series the IAEA-

TECDOC Series the Training Course Series and the IAEA Services Series and as

Practical Radiation Safety Manuals and Practical Radiation Technical Manuals Security

related publications are issued in the IAEA Nuclear Security Series

FOREWORD

by Yukiya Amano

Director General

EDITORIAL NOTE

CONTENTS

1 INTRODUCTION 11

BACKGROUND 11

OBJECTIVE 33

SCOPE 33

STRUCTURE 44

2 OVERVIEW OF MONITORING AND SURVEILLANCE 55

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES 66

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY REGARDING

MONITORING AND SURVEILLANCE PROGRAMMES 99

RESPONSIBILITIES OF THE OPERATOR 99

RESPONSIBILITIES OF THE REGULATORY BODY 99

4 DESIGN OF A MONITORING PROGRAMME 1313

5 MONITORING BY TYPE OF DISPOSAL FACILITY 1919

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME 2121

MONITORING FOR EMERGENCY RESPONSE 2424

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE

PROGRAMME 2727

TYPE AND FREQUENCY OF INSPECTIONS 2828

8 USE OF MONITORING AND SURVEILLANCE INFORMATION 3131

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES 3131

DEVIATIONS FROM EXPECTED RESULTS 3333

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE

PROGRAMME 3434

9 MANAGEMENT SYSTEM 3535

ANNEX I 3939

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION

COLLECTED FOR A GEOLOGICAL DISPOSAL PROGRAMME 3939

ANNEX II 5151

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FOR A NEAR SURFACE

DISPOSAL PROGRAMME 5151

1

1 INTRODUCTION

BACKGROUND

11 Radioactive waste arises from the generation of electricity in nuclear power plants from

nuclear fuel cycle operations and from other activities in the nuclear fuel cycle such as mining and

milling of uranium and thorium ores Radioactive waste also arises in a wide range of industrial and

medical activities It also arises from activities and processes in which radioactive materials of natural

origin become concentrated in waste material and safety needs to be considered in its management

12 A monitoring and surveillance programme is an important element in providing reassurance

that a disposal facility for radioactive waste provides the required level of safety during its operational

period and post-closure period depending on the type of the disposal The safety principles to be

applied in all radioactive waste management activities are set out in the IAEA Fundamental Safety

Principles [1] Within the safety standards series the safety requirements for Near Surface Disposal of

Radioactive Waste [2] and Geological Disposal of Radioactive Waste [3] providing specific

monitoring requirements for their respective types of facilities have been combined to create a single

safety standard for Disposal of Radioactive Waste [4]

13 The IAEA is also developing a Safety Guide on geological disposal facilities for radioactive

waste [5] and is preparing a Safety Guide on near surface disposal facilities for radioactive wastes [6]

as well as a Safety Guide on the protection of the public against exposure to natural sources of

radiation including NORM residues [7] The present Safety Guide provides support for these safety

standards in the area of monitoring and surveillance

14 Differing kinds of monitoring activities occur in each period of the lifetime of a radioactive

waste disposal facility This Safety Guide covers monitoring and surveillance during pre-operational

operational and post-closure periods for near surface geological and mine waste disposal facilities

These periods are defined as follows [4]

minus The pre-operational period includes concept definition site evaluation (selection

verification and confirmation) safety assessment and design studies It also includes the

development of those aspects of the safety case for safety in operation and after closure

that are required in order to set the conditions of authorization to obtain the authorization

and to proceed with the construction of the disposal facility and the initial operational

activities The monitoring and testing programmes that are needed to inform operational

management decisions are put in place

minus The operational period begins when waste is first received at the facility From this time

radiation exposures may occur as a result of waste management activities and these are

subject to control in accordance with the requirements for protection and safety

2

Monitoring surveillance and testing programmes continue to inform operational

management decisions and to provide the basis for decisions concerning the closure of

the facility or parts of it Safety assessments for the period of operation and after closure

and the safety case are updated as necessary to reflect actual experience and increasing

knowledge In the operational period construction activities may take place at the same

time as waste emplacement in and closure of other parts of the facility This period may

include activities for waste retrieval mdash if considered necessary mdash prior to closure

activities following the completion of waste emplacement and the final closure and

sealing of the facility

minus The post-closure period begins at the time when all the engineered containment and

isolation features have been put in place operational buildings and supporting services

have been decommissioned and the facility is in its final configuration After its closure

the safety of the disposal facility is provided for by means of passive features inherent in

the characteristics of the site and the facility and characteristics of the waste packages

together with certain institutional controls particularly for near surface facilities Such

institutional controls are put in place to prevent intrusion into facilities and to confirm

that the disposal system is performing as expected by means of monitoring and

surveillance Monitoring may also be carried out to provide public assurance The licence

will be terminated after the period of active institutional control when all the necessary

technical legal and financial requirements have been fulfilled

15 The International Basic Safety Standards for Protection against Ionizing Radiation and for the

Safety of Radiation Sources (the BSS) [8] and the IAEA Safety Guide for environmental and source

monitoring for purposes of radiation protection Ref [9] provide a framework for all generic aspects of

radiological monitoring In particular Ref [8] establishes the basic requirements for radiological

monitoring of public exposure and Ref [9] covers pre-operational monitoring operational monitoring

(including decommissioning) and post-closure radiological monitoring It also acknowledges the need

for monitoring a variety of non-radiological variables The present Safety Guide is intended to

elaborate upon the requirements in the BSS and to complement the guidance provided in Ref [9] in

particular in regard to performance monitoring aspects of disposal facility development On matters

pertaining to source and environmental monitoring the present Safety Guide is subsidiary to and

defers to Ref [9]

16 The draft International Basic Safety Standards currently under development to supersede Ref

[8] will contain an updated and extended set of requirements on the regulatory control and monitoring

of public exposure and safety of the radioactive waste management

17 There are presently four IAEA publications concerned with monitoring and surveillance of

disposal facilities Safety Reports Series No 27 on Monitoring and Surveillance of Residues from the

3

Mining and Milling of Uranium and Thorium [10] Safety Reports Series No 35 on Surveillance and

Monitoring of Near Surface Disposal Facilities for Radioactive Waste [11] Safety Reports Series No

64 on Programmes and Systems for Source and Environmental Radiation Monitoring [18] and IAEA-

TECDOC-1208 on Monitoring of Geological Repositories for High Level Radioactive Waste [12]

These publications have served as resources for development of the present Safety Guide

OBJECTIVE

18 The objective of this Safety Guide is to provide guidance for monitoring and surveillance of

radioactive waste disposal facilities during their entire lifetime The Safety Guide includes the

different objectives that monitoring has at the lifetime periods from initiation of work on a candidate

site to the period after closure of the disposal facility

SCOPE

19 This Safety Guide considers the monitoring and surveillance of three types of disposal

facilities

bull Near surface disposal facilities

bull Geological disposal facilities

bull Disposal facilities for uranium and thorium mine waste

The three types of disposal facilities listed above are considered to cover all the disposal options as

identified in the Safety Requirements on Disposal of Radioactive Waste [4] In this Safety Guide

borehole disposal facilities are not specifically addressed However borehole disposal is not

conceptually different from either near surface disposal or geological disposal of radioactive waste A

possible surveillance and monitoring programme suitable for a small scale borehole disposal facility is

discussed in other IAEA Safety Standards [20]

110 As explained in Ref [14] the term near surface disposal refers generally to disposal at or

within a few tens of metres of the ground surface The term geological disposal generally refers to

disposal in deep stable geological formations usually several hundred meters or more below the

surface Mining waste disposal facilities cover a spectrum of designs from above-grade mounds to

geological disposal of tailings slimes sometimes used as backfill in old mine workings The type of

disposal is controlled by the waste characteristics and in any case the suitability of waste for disposal

in a particular disposal facility is required to be demonstrated by the safety case and supporting safety

assessment for the facility From the safety point of view disposal depth is one of the factors

considered in assessing the safety of disposal the geological environment the waste characteristics

4

and engineered features are of equal or more importance than depth of disposal in assessing the safety

of disposal facility

111 This Safety Guide places emphasis on an approach to monitoring and surveillance that

provides data needed for the development of the safety case The safety case includes information

needed for siting construct operate and close the facility for supporting decisions on managing the

disposal programme as well as information that are of particular interest to interested parties [4]

Technical details on monitoring and surveillance methodologies are beyond the scope of this Safety

Guide however Refs [10 11 12 18] direct the reader to such information and Annexes I and II give

examples of monitoring programmes for geological and near surface disposal programmes

112 This Safety Guide does not specifically address monitoring that will be required for

bull Operating personnel

bull Waste characterization or tracking

bull Nuclear materials control in the case of facilities that will contain significant quantities of

nuclear materials

Nor does it focus on monitoring for non-radiological contaminants that may be of potential concern

Facility operators however should consider such contaminants when designing their monitoring

programme

113 This Safety Guide does not address monitoring for occupational exposure rather the focus is

on monitoring for disposal system performance and radiation protection of the public and the

environment Monitoring for occupational radiation protection is discussed in other IAEA safety

standards [13]

STRUCTURE

114 Section 2 provides an overview of monitoring and surveillance for radioactive waste disposal

facilities and describes overall objectives for a monitoring and surveillance programme Section 3

addresses roles and responsibilities of the regulatory body and the implementing organizations with

regard to monitoring and surveillance Sections 4 5 and 6 focus on monitoring More specifically

Section 4 addresses design of a monitoring programme and includes some consideration of strategic

issues for monitoring Section 5 provides guidance on monitoring according to the type of disposal

facility (geological near surface and facilities for mining and milling waste) Section 6 addresses

monitoring according to the stage of facility development Section 7 provides specific guidance for

surveillance activities only Finally Section 8 is concerned with the use of monitoring and surveillance

information in regard to compliance aspects and development and improvement of the safety case and

Section 9 provides a brief discussion of the salient issues pertaining to the management system for a

disposal facility

5

2 OVERVIEW OF MONITORING AND SURVEILLANCE

21 The BSS [8] defines lsquomonitoringrsquo (of public exposure) to be

ldquoThe measurement of dose or contamination for reasons related to the assessment or

control of exposure to radiation or radioactive substances and the interpretation of the

resultsrdquo

22 The IAEA Safety Guide on environmental and source monitoring [9] defines the terms lsquosource

monitoringrsquo and lsquoenvironmental monitoringrsquo as

a ldquoSource monitoring The measurement of activity in radioactive materials being

released to the environment or of external dose rates due to sources within a facility or

activityrdquo

b ldquoEnvironmental monitoring The measurement of external dose rates due to sources in

the environment or of radionuclide concentrations in environmental mediardquo

23 In the context of this Safety Guide the term monitoring refers to

Continuous or periodic observations and measurements of environmental engineering or

radiological parameters to help evaluate the behaviour of components of the waste

disposal system or of the impacts of the waste disposal system and its operation on the

public and the environment

24 Monitoring involves many characterization activities Information may have to be collected

over a period of time for a number of characterization tasks (eg groundwater flow rates moisture

content of soils daily precipitation) For other types of information once the parameter has been

defined there may be no need to continue with the sampling and measurement since it is not expected

to change in time or with development and closure of the facility (eg rock porosity)

25 Monitoring is needed to evaluate processes or parameters that are influential in the

development of the safety case The duration and frequency of monitoring may be determined by

regulatory requirements by the time scale of natural variations in a process or parameter by possible

changes associated with the construction and operation of the facility The need to address public

concern should also be considered in defining the monitoring programme

26 A programme for the surveillance of the facility should be established and implemented as

necessary and feasible It should consist of planned activities carried out to verify that the facility is

operating within the design limits and conditions and to detect any deterioration of structures systems

and components that could result in unsafe conditions [17] In the context of this Safety Guide the

term surveillance refers to

6

The physical inspection of a waste management facility in order to verify its integrity to

protect and preserve the passive safety barriers

27 Some countries do not differentiate between monitoring and surveillance of disposal facilities

28 In this respect the function of surveillance is to contribute to the detection of changes in the

engineering structures and systems of the disposal facility which might affect the radiological

performance of the system The relevant and expected changes can be identified by the post closure

safety assessment The surveillance programme is usually implemented through regular inspections of

the critical components of the waste disposal facility

29 Generally there is a need to collect site-specific data although some relevant monitoring data

may be available from other sources Safety cases are usually supported by data from a number of

sources which includes site-specific measurements regional data and generic information

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES

210 Requirement 21 of the Safety Requirements on the Disposal of Radioactive Waste [4] states

that ldquoA programme of monitoring shall be carried out prior to and during the construction and

operation of a disposal facility and after its closure if this is part of the safety case This programme

shall be designed to collect and update information necessary for the purposes of protection and safety

Information shall be obtained to confirm the conditions necessary for the safety of workers and

members of the public and protection of the environment during the period of operation of the facility

Monitoring shall also be carried out to confirm the absence of any conditions that could affect the

safety of the facility after closurerdquo

211 In addition Requirement 10 of Ref [4] indicates that ldquoAn appropriate level of surveillance and

control shall be applied to protect and preserve the passive safety features to the extent that this is

necessary so that they can fulfil the functions that they are assigned in the safety case for safety after

closurerdquo

212 Monitoring and surveillance programmes begin at site characterization phase of disposal

facility development and continue to evolve through to the post-closure period depending on the type

of the disposal facility The data collected and insights derived from monitoring should be integrated

into and inform planning decisions made throughout the life-cycle of a disposal facility As a result

provision should be made to anticipate the needs of monitoring at later periods of the facility lifetime

and to gather monitoring data that informs later planning and actions

213 Monitoring and surveillance of disposal facilities for radioactive waste has four broad

objectives

7

1 To demonstrate compliance with the regulatory constraints and licence conditions

2 To verify that the disposal system is functioning as expected This means that the components

fulfil their function as identified in the safety case and that actual conditions are consistent

with the assumptions made for post-closure safety

3 To strengthen understanding of aspects of system behaviour used in developing the safety case

for the dispoal facility and to allow further testing of models predicting those aspects

4 To accumulate an environmental database of the site the disposal facility and its surroundings

for future decisions that are part of a stepwise programme of construction operation and

closure of the disposal facility

214 As mentioned in Ref [4] ldquoMonitoring programmes are designed and implemented so as not to

reduce the overall level of safety of the facility after closurerdquo (para 54) ldquoTo some extent the safety of

a disposal facility can depend on some future actions such as maintenance work or surveillance

However this dependence has to be minimized to the extent possiblerdquo (para 322) ldquoFor a geological

disposal facility it is possible to provide for safety after closure by means of passive features In the

case of a near surface disposal facility actions such as maintenance monitoring or surveillance may

be necessary for a period of time after closure to ensure safetyrdquo (para 323)

215 The monitoring programme should be closely tied to the safety case Even if safety should not

rely on monitoring and surveillance the results of such a programme should be used to strengthen the

safety case and build confidence in safety As well information needs of the safety case should be

used to improve the monitoring program

216 Requirement 7 of Ref [4] indicates that ldquoThe host environment shall be selected the

engineered barriers of the disposal facility shall be designed and the facility shall be operated to ensure

that safety is provided by means of multiple safety functions Containment and isolation of the waste

shall be provided by means of a number of physical barriers of the disposal systemrdquo The monitoring

and surveillance programme should provide to the extent practical the necessary information to

ensure that each barrier and its associated safety function(s) performs as planned and indicated in the

safety case In addition the monitoring and surveillance programme should confirm that the

performances of the engineered and natural barriers are not damaged by the operational activities

217 Further to its technical objectives a monitoring and surveillance programme can be a suitable

tool for public reassurance In that sense consideration of public interest and interested parties

concerns may provide useful information to improve the monitoring programme by including social

aspects

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 6: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

FOREWORD

by Yukiya Amano

Director General

EDITORIAL NOTE

CONTENTS

1 INTRODUCTION 11

BACKGROUND 11

OBJECTIVE 33

SCOPE 33

STRUCTURE 44

2 OVERVIEW OF MONITORING AND SURVEILLANCE 55

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES 66

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY REGARDING

MONITORING AND SURVEILLANCE PROGRAMMES 99

RESPONSIBILITIES OF THE OPERATOR 99

RESPONSIBILITIES OF THE REGULATORY BODY 99

4 DESIGN OF A MONITORING PROGRAMME 1313

5 MONITORING BY TYPE OF DISPOSAL FACILITY 1919

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME 2121

MONITORING FOR EMERGENCY RESPONSE 2424

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE

PROGRAMME 2727

TYPE AND FREQUENCY OF INSPECTIONS 2828

8 USE OF MONITORING AND SURVEILLANCE INFORMATION 3131

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES 3131

DEVIATIONS FROM EXPECTED RESULTS 3333

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE

PROGRAMME 3434

9 MANAGEMENT SYSTEM 3535

ANNEX I 3939

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION

COLLECTED FOR A GEOLOGICAL DISPOSAL PROGRAMME 3939

ANNEX II 5151

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FOR A NEAR SURFACE

DISPOSAL PROGRAMME 5151

1

1 INTRODUCTION

BACKGROUND

11 Radioactive waste arises from the generation of electricity in nuclear power plants from

nuclear fuel cycle operations and from other activities in the nuclear fuel cycle such as mining and

milling of uranium and thorium ores Radioactive waste also arises in a wide range of industrial and

medical activities It also arises from activities and processes in which radioactive materials of natural

origin become concentrated in waste material and safety needs to be considered in its management

12 A monitoring and surveillance programme is an important element in providing reassurance

that a disposal facility for radioactive waste provides the required level of safety during its operational

period and post-closure period depending on the type of the disposal The safety principles to be

applied in all radioactive waste management activities are set out in the IAEA Fundamental Safety

Principles [1] Within the safety standards series the safety requirements for Near Surface Disposal of

Radioactive Waste [2] and Geological Disposal of Radioactive Waste [3] providing specific

monitoring requirements for their respective types of facilities have been combined to create a single

safety standard for Disposal of Radioactive Waste [4]

13 The IAEA is also developing a Safety Guide on geological disposal facilities for radioactive

waste [5] and is preparing a Safety Guide on near surface disposal facilities for radioactive wastes [6]

as well as a Safety Guide on the protection of the public against exposure to natural sources of

radiation including NORM residues [7] The present Safety Guide provides support for these safety

standards in the area of monitoring and surveillance

14 Differing kinds of monitoring activities occur in each period of the lifetime of a radioactive

waste disposal facility This Safety Guide covers monitoring and surveillance during pre-operational

operational and post-closure periods for near surface geological and mine waste disposal facilities

These periods are defined as follows [4]

minus The pre-operational period includes concept definition site evaluation (selection

verification and confirmation) safety assessment and design studies It also includes the

development of those aspects of the safety case for safety in operation and after closure

that are required in order to set the conditions of authorization to obtain the authorization

and to proceed with the construction of the disposal facility and the initial operational

activities The monitoring and testing programmes that are needed to inform operational

management decisions are put in place

minus The operational period begins when waste is first received at the facility From this time

radiation exposures may occur as a result of waste management activities and these are

subject to control in accordance with the requirements for protection and safety

2

Monitoring surveillance and testing programmes continue to inform operational

management decisions and to provide the basis for decisions concerning the closure of

the facility or parts of it Safety assessments for the period of operation and after closure

and the safety case are updated as necessary to reflect actual experience and increasing

knowledge In the operational period construction activities may take place at the same

time as waste emplacement in and closure of other parts of the facility This period may

include activities for waste retrieval mdash if considered necessary mdash prior to closure

activities following the completion of waste emplacement and the final closure and

sealing of the facility

minus The post-closure period begins at the time when all the engineered containment and

isolation features have been put in place operational buildings and supporting services

have been decommissioned and the facility is in its final configuration After its closure

the safety of the disposal facility is provided for by means of passive features inherent in

the characteristics of the site and the facility and characteristics of the waste packages

together with certain institutional controls particularly for near surface facilities Such

institutional controls are put in place to prevent intrusion into facilities and to confirm

that the disposal system is performing as expected by means of monitoring and

surveillance Monitoring may also be carried out to provide public assurance The licence

will be terminated after the period of active institutional control when all the necessary

technical legal and financial requirements have been fulfilled

15 The International Basic Safety Standards for Protection against Ionizing Radiation and for the

Safety of Radiation Sources (the BSS) [8] and the IAEA Safety Guide for environmental and source

monitoring for purposes of radiation protection Ref [9] provide a framework for all generic aspects of

radiological monitoring In particular Ref [8] establishes the basic requirements for radiological

monitoring of public exposure and Ref [9] covers pre-operational monitoring operational monitoring

(including decommissioning) and post-closure radiological monitoring It also acknowledges the need

for monitoring a variety of non-radiological variables The present Safety Guide is intended to

elaborate upon the requirements in the BSS and to complement the guidance provided in Ref [9] in

particular in regard to performance monitoring aspects of disposal facility development On matters

pertaining to source and environmental monitoring the present Safety Guide is subsidiary to and

defers to Ref [9]

16 The draft International Basic Safety Standards currently under development to supersede Ref

[8] will contain an updated and extended set of requirements on the regulatory control and monitoring

of public exposure and safety of the radioactive waste management

17 There are presently four IAEA publications concerned with monitoring and surveillance of

disposal facilities Safety Reports Series No 27 on Monitoring and Surveillance of Residues from the

3

Mining and Milling of Uranium and Thorium [10] Safety Reports Series No 35 on Surveillance and

Monitoring of Near Surface Disposal Facilities for Radioactive Waste [11] Safety Reports Series No

64 on Programmes and Systems for Source and Environmental Radiation Monitoring [18] and IAEA-

TECDOC-1208 on Monitoring of Geological Repositories for High Level Radioactive Waste [12]

These publications have served as resources for development of the present Safety Guide

OBJECTIVE

18 The objective of this Safety Guide is to provide guidance for monitoring and surveillance of

radioactive waste disposal facilities during their entire lifetime The Safety Guide includes the

different objectives that monitoring has at the lifetime periods from initiation of work on a candidate

site to the period after closure of the disposal facility

SCOPE

19 This Safety Guide considers the monitoring and surveillance of three types of disposal

facilities

bull Near surface disposal facilities

bull Geological disposal facilities

bull Disposal facilities for uranium and thorium mine waste

The three types of disposal facilities listed above are considered to cover all the disposal options as

identified in the Safety Requirements on Disposal of Radioactive Waste [4] In this Safety Guide

borehole disposal facilities are not specifically addressed However borehole disposal is not

conceptually different from either near surface disposal or geological disposal of radioactive waste A

possible surveillance and monitoring programme suitable for a small scale borehole disposal facility is

discussed in other IAEA Safety Standards [20]

110 As explained in Ref [14] the term near surface disposal refers generally to disposal at or

within a few tens of metres of the ground surface The term geological disposal generally refers to

disposal in deep stable geological formations usually several hundred meters or more below the

surface Mining waste disposal facilities cover a spectrum of designs from above-grade mounds to

geological disposal of tailings slimes sometimes used as backfill in old mine workings The type of

disposal is controlled by the waste characteristics and in any case the suitability of waste for disposal

in a particular disposal facility is required to be demonstrated by the safety case and supporting safety

assessment for the facility From the safety point of view disposal depth is one of the factors

considered in assessing the safety of disposal the geological environment the waste characteristics

4

and engineered features are of equal or more importance than depth of disposal in assessing the safety

of disposal facility

111 This Safety Guide places emphasis on an approach to monitoring and surveillance that

provides data needed for the development of the safety case The safety case includes information

needed for siting construct operate and close the facility for supporting decisions on managing the

disposal programme as well as information that are of particular interest to interested parties [4]

Technical details on monitoring and surveillance methodologies are beyond the scope of this Safety

Guide however Refs [10 11 12 18] direct the reader to such information and Annexes I and II give

examples of monitoring programmes for geological and near surface disposal programmes

112 This Safety Guide does not specifically address monitoring that will be required for

bull Operating personnel

bull Waste characterization or tracking

bull Nuclear materials control in the case of facilities that will contain significant quantities of

nuclear materials

Nor does it focus on monitoring for non-radiological contaminants that may be of potential concern

Facility operators however should consider such contaminants when designing their monitoring

programme

113 This Safety Guide does not address monitoring for occupational exposure rather the focus is

on monitoring for disposal system performance and radiation protection of the public and the

environment Monitoring for occupational radiation protection is discussed in other IAEA safety

standards [13]

STRUCTURE

114 Section 2 provides an overview of monitoring and surveillance for radioactive waste disposal

facilities and describes overall objectives for a monitoring and surveillance programme Section 3

addresses roles and responsibilities of the regulatory body and the implementing organizations with

regard to monitoring and surveillance Sections 4 5 and 6 focus on monitoring More specifically

Section 4 addresses design of a monitoring programme and includes some consideration of strategic

issues for monitoring Section 5 provides guidance on monitoring according to the type of disposal

facility (geological near surface and facilities for mining and milling waste) Section 6 addresses

monitoring according to the stage of facility development Section 7 provides specific guidance for

surveillance activities only Finally Section 8 is concerned with the use of monitoring and surveillance

information in regard to compliance aspects and development and improvement of the safety case and

Section 9 provides a brief discussion of the salient issues pertaining to the management system for a

disposal facility

5

2 OVERVIEW OF MONITORING AND SURVEILLANCE

21 The BSS [8] defines lsquomonitoringrsquo (of public exposure) to be

ldquoThe measurement of dose or contamination for reasons related to the assessment or

control of exposure to radiation or radioactive substances and the interpretation of the

resultsrdquo

22 The IAEA Safety Guide on environmental and source monitoring [9] defines the terms lsquosource

monitoringrsquo and lsquoenvironmental monitoringrsquo as

a ldquoSource monitoring The measurement of activity in radioactive materials being

released to the environment or of external dose rates due to sources within a facility or

activityrdquo

b ldquoEnvironmental monitoring The measurement of external dose rates due to sources in

the environment or of radionuclide concentrations in environmental mediardquo

23 In the context of this Safety Guide the term monitoring refers to

Continuous or periodic observations and measurements of environmental engineering or

radiological parameters to help evaluate the behaviour of components of the waste

disposal system or of the impacts of the waste disposal system and its operation on the

public and the environment

24 Monitoring involves many characterization activities Information may have to be collected

over a period of time for a number of characterization tasks (eg groundwater flow rates moisture

content of soils daily precipitation) For other types of information once the parameter has been

defined there may be no need to continue with the sampling and measurement since it is not expected

to change in time or with development and closure of the facility (eg rock porosity)

25 Monitoring is needed to evaluate processes or parameters that are influential in the

development of the safety case The duration and frequency of monitoring may be determined by

regulatory requirements by the time scale of natural variations in a process or parameter by possible

changes associated with the construction and operation of the facility The need to address public

concern should also be considered in defining the monitoring programme

26 A programme for the surveillance of the facility should be established and implemented as

necessary and feasible It should consist of planned activities carried out to verify that the facility is

operating within the design limits and conditions and to detect any deterioration of structures systems

and components that could result in unsafe conditions [17] In the context of this Safety Guide the

term surveillance refers to

6

The physical inspection of a waste management facility in order to verify its integrity to

protect and preserve the passive safety barriers

27 Some countries do not differentiate between monitoring and surveillance of disposal facilities

28 In this respect the function of surveillance is to contribute to the detection of changes in the

engineering structures and systems of the disposal facility which might affect the radiological

performance of the system The relevant and expected changes can be identified by the post closure

safety assessment The surveillance programme is usually implemented through regular inspections of

the critical components of the waste disposal facility

29 Generally there is a need to collect site-specific data although some relevant monitoring data

may be available from other sources Safety cases are usually supported by data from a number of

sources which includes site-specific measurements regional data and generic information

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES

210 Requirement 21 of the Safety Requirements on the Disposal of Radioactive Waste [4] states

that ldquoA programme of monitoring shall be carried out prior to and during the construction and

operation of a disposal facility and after its closure if this is part of the safety case This programme

shall be designed to collect and update information necessary for the purposes of protection and safety

Information shall be obtained to confirm the conditions necessary for the safety of workers and

members of the public and protection of the environment during the period of operation of the facility

Monitoring shall also be carried out to confirm the absence of any conditions that could affect the

safety of the facility after closurerdquo

211 In addition Requirement 10 of Ref [4] indicates that ldquoAn appropriate level of surveillance and

control shall be applied to protect and preserve the passive safety features to the extent that this is

necessary so that they can fulfil the functions that they are assigned in the safety case for safety after

closurerdquo

212 Monitoring and surveillance programmes begin at site characterization phase of disposal

facility development and continue to evolve through to the post-closure period depending on the type

of the disposal facility The data collected and insights derived from monitoring should be integrated

into and inform planning decisions made throughout the life-cycle of a disposal facility As a result

provision should be made to anticipate the needs of monitoring at later periods of the facility lifetime

and to gather monitoring data that informs later planning and actions

213 Monitoring and surveillance of disposal facilities for radioactive waste has four broad

objectives

7

1 To demonstrate compliance with the regulatory constraints and licence conditions

2 To verify that the disposal system is functioning as expected This means that the components

fulfil their function as identified in the safety case and that actual conditions are consistent

with the assumptions made for post-closure safety

3 To strengthen understanding of aspects of system behaviour used in developing the safety case

for the dispoal facility and to allow further testing of models predicting those aspects

4 To accumulate an environmental database of the site the disposal facility and its surroundings

for future decisions that are part of a stepwise programme of construction operation and

closure of the disposal facility

214 As mentioned in Ref [4] ldquoMonitoring programmes are designed and implemented so as not to

reduce the overall level of safety of the facility after closurerdquo (para 54) ldquoTo some extent the safety of

a disposal facility can depend on some future actions such as maintenance work or surveillance

However this dependence has to be minimized to the extent possiblerdquo (para 322) ldquoFor a geological

disposal facility it is possible to provide for safety after closure by means of passive features In the

case of a near surface disposal facility actions such as maintenance monitoring or surveillance may

be necessary for a period of time after closure to ensure safetyrdquo (para 323)

215 The monitoring programme should be closely tied to the safety case Even if safety should not

rely on monitoring and surveillance the results of such a programme should be used to strengthen the

safety case and build confidence in safety As well information needs of the safety case should be

used to improve the monitoring program

216 Requirement 7 of Ref [4] indicates that ldquoThe host environment shall be selected the

engineered barriers of the disposal facility shall be designed and the facility shall be operated to ensure

that safety is provided by means of multiple safety functions Containment and isolation of the waste

shall be provided by means of a number of physical barriers of the disposal systemrdquo The monitoring

and surveillance programme should provide to the extent practical the necessary information to

ensure that each barrier and its associated safety function(s) performs as planned and indicated in the

safety case In addition the monitoring and surveillance programme should confirm that the

performances of the engineered and natural barriers are not damaged by the operational activities

217 Further to its technical objectives a monitoring and surveillance programme can be a suitable

tool for public reassurance In that sense consideration of public interest and interested parties

concerns may provide useful information to improve the monitoring programme by including social

aspects

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 7: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

EDITORIAL NOTE

CONTENTS

1 INTRODUCTION 11

BACKGROUND 11

OBJECTIVE 33

SCOPE 33

STRUCTURE 44

2 OVERVIEW OF MONITORING AND SURVEILLANCE 55

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES 66

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY REGARDING

MONITORING AND SURVEILLANCE PROGRAMMES 99

RESPONSIBILITIES OF THE OPERATOR 99

RESPONSIBILITIES OF THE REGULATORY BODY 99

4 DESIGN OF A MONITORING PROGRAMME 1313

5 MONITORING BY TYPE OF DISPOSAL FACILITY 1919

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME 2121

MONITORING FOR EMERGENCY RESPONSE 2424

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE

PROGRAMME 2727

TYPE AND FREQUENCY OF INSPECTIONS 2828

8 USE OF MONITORING AND SURVEILLANCE INFORMATION 3131

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES 3131

DEVIATIONS FROM EXPECTED RESULTS 3333

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE

PROGRAMME 3434

9 MANAGEMENT SYSTEM 3535

ANNEX I 3939

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION

COLLECTED FOR A GEOLOGICAL DISPOSAL PROGRAMME 3939

ANNEX II 5151

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FOR A NEAR SURFACE

DISPOSAL PROGRAMME 5151

1

1 INTRODUCTION

BACKGROUND

11 Radioactive waste arises from the generation of electricity in nuclear power plants from

nuclear fuel cycle operations and from other activities in the nuclear fuel cycle such as mining and

milling of uranium and thorium ores Radioactive waste also arises in a wide range of industrial and

medical activities It also arises from activities and processes in which radioactive materials of natural

origin become concentrated in waste material and safety needs to be considered in its management

12 A monitoring and surveillance programme is an important element in providing reassurance

that a disposal facility for radioactive waste provides the required level of safety during its operational

period and post-closure period depending on the type of the disposal The safety principles to be

applied in all radioactive waste management activities are set out in the IAEA Fundamental Safety

Principles [1] Within the safety standards series the safety requirements for Near Surface Disposal of

Radioactive Waste [2] and Geological Disposal of Radioactive Waste [3] providing specific

monitoring requirements for their respective types of facilities have been combined to create a single

safety standard for Disposal of Radioactive Waste [4]

13 The IAEA is also developing a Safety Guide on geological disposal facilities for radioactive

waste [5] and is preparing a Safety Guide on near surface disposal facilities for radioactive wastes [6]

as well as a Safety Guide on the protection of the public against exposure to natural sources of

radiation including NORM residues [7] The present Safety Guide provides support for these safety

standards in the area of monitoring and surveillance

14 Differing kinds of monitoring activities occur in each period of the lifetime of a radioactive

waste disposal facility This Safety Guide covers monitoring and surveillance during pre-operational

operational and post-closure periods for near surface geological and mine waste disposal facilities

These periods are defined as follows [4]

minus The pre-operational period includes concept definition site evaluation (selection

verification and confirmation) safety assessment and design studies It also includes the

development of those aspects of the safety case for safety in operation and after closure

that are required in order to set the conditions of authorization to obtain the authorization

and to proceed with the construction of the disposal facility and the initial operational

activities The monitoring and testing programmes that are needed to inform operational

management decisions are put in place

minus The operational period begins when waste is first received at the facility From this time

radiation exposures may occur as a result of waste management activities and these are

subject to control in accordance with the requirements for protection and safety

2

Monitoring surveillance and testing programmes continue to inform operational

management decisions and to provide the basis for decisions concerning the closure of

the facility or parts of it Safety assessments for the period of operation and after closure

and the safety case are updated as necessary to reflect actual experience and increasing

knowledge In the operational period construction activities may take place at the same

time as waste emplacement in and closure of other parts of the facility This period may

include activities for waste retrieval mdash if considered necessary mdash prior to closure

activities following the completion of waste emplacement and the final closure and

sealing of the facility

minus The post-closure period begins at the time when all the engineered containment and

isolation features have been put in place operational buildings and supporting services

have been decommissioned and the facility is in its final configuration After its closure

the safety of the disposal facility is provided for by means of passive features inherent in

the characteristics of the site and the facility and characteristics of the waste packages

together with certain institutional controls particularly for near surface facilities Such

institutional controls are put in place to prevent intrusion into facilities and to confirm

that the disposal system is performing as expected by means of monitoring and

surveillance Monitoring may also be carried out to provide public assurance The licence

will be terminated after the period of active institutional control when all the necessary

technical legal and financial requirements have been fulfilled

15 The International Basic Safety Standards for Protection against Ionizing Radiation and for the

Safety of Radiation Sources (the BSS) [8] and the IAEA Safety Guide for environmental and source

monitoring for purposes of radiation protection Ref [9] provide a framework for all generic aspects of

radiological monitoring In particular Ref [8] establishes the basic requirements for radiological

monitoring of public exposure and Ref [9] covers pre-operational monitoring operational monitoring

(including decommissioning) and post-closure radiological monitoring It also acknowledges the need

for monitoring a variety of non-radiological variables The present Safety Guide is intended to

elaborate upon the requirements in the BSS and to complement the guidance provided in Ref [9] in

particular in regard to performance monitoring aspects of disposal facility development On matters

pertaining to source and environmental monitoring the present Safety Guide is subsidiary to and

defers to Ref [9]

16 The draft International Basic Safety Standards currently under development to supersede Ref

[8] will contain an updated and extended set of requirements on the regulatory control and monitoring

of public exposure and safety of the radioactive waste management

17 There are presently four IAEA publications concerned with monitoring and surveillance of

disposal facilities Safety Reports Series No 27 on Monitoring and Surveillance of Residues from the

3

Mining and Milling of Uranium and Thorium [10] Safety Reports Series No 35 on Surveillance and

Monitoring of Near Surface Disposal Facilities for Radioactive Waste [11] Safety Reports Series No

64 on Programmes and Systems for Source and Environmental Radiation Monitoring [18] and IAEA-

TECDOC-1208 on Monitoring of Geological Repositories for High Level Radioactive Waste [12]

These publications have served as resources for development of the present Safety Guide

OBJECTIVE

18 The objective of this Safety Guide is to provide guidance for monitoring and surveillance of

radioactive waste disposal facilities during their entire lifetime The Safety Guide includes the

different objectives that monitoring has at the lifetime periods from initiation of work on a candidate

site to the period after closure of the disposal facility

SCOPE

19 This Safety Guide considers the monitoring and surveillance of three types of disposal

facilities

bull Near surface disposal facilities

bull Geological disposal facilities

bull Disposal facilities for uranium and thorium mine waste

The three types of disposal facilities listed above are considered to cover all the disposal options as

identified in the Safety Requirements on Disposal of Radioactive Waste [4] In this Safety Guide

borehole disposal facilities are not specifically addressed However borehole disposal is not

conceptually different from either near surface disposal or geological disposal of radioactive waste A

possible surveillance and monitoring programme suitable for a small scale borehole disposal facility is

discussed in other IAEA Safety Standards [20]

110 As explained in Ref [14] the term near surface disposal refers generally to disposal at or

within a few tens of metres of the ground surface The term geological disposal generally refers to

disposal in deep stable geological formations usually several hundred meters or more below the

surface Mining waste disposal facilities cover a spectrum of designs from above-grade mounds to

geological disposal of tailings slimes sometimes used as backfill in old mine workings The type of

disposal is controlled by the waste characteristics and in any case the suitability of waste for disposal

in a particular disposal facility is required to be demonstrated by the safety case and supporting safety

assessment for the facility From the safety point of view disposal depth is one of the factors

considered in assessing the safety of disposal the geological environment the waste characteristics

4

and engineered features are of equal or more importance than depth of disposal in assessing the safety

of disposal facility

111 This Safety Guide places emphasis on an approach to monitoring and surveillance that

provides data needed for the development of the safety case The safety case includes information

needed for siting construct operate and close the facility for supporting decisions on managing the

disposal programme as well as information that are of particular interest to interested parties [4]

Technical details on monitoring and surveillance methodologies are beyond the scope of this Safety

Guide however Refs [10 11 12 18] direct the reader to such information and Annexes I and II give

examples of monitoring programmes for geological and near surface disposal programmes

112 This Safety Guide does not specifically address monitoring that will be required for

bull Operating personnel

bull Waste characterization or tracking

bull Nuclear materials control in the case of facilities that will contain significant quantities of

nuclear materials

Nor does it focus on monitoring for non-radiological contaminants that may be of potential concern

Facility operators however should consider such contaminants when designing their monitoring

programme

113 This Safety Guide does not address monitoring for occupational exposure rather the focus is

on monitoring for disposal system performance and radiation protection of the public and the

environment Monitoring for occupational radiation protection is discussed in other IAEA safety

standards [13]

STRUCTURE

114 Section 2 provides an overview of monitoring and surveillance for radioactive waste disposal

facilities and describes overall objectives for a monitoring and surveillance programme Section 3

addresses roles and responsibilities of the regulatory body and the implementing organizations with

regard to monitoring and surveillance Sections 4 5 and 6 focus on monitoring More specifically

Section 4 addresses design of a monitoring programme and includes some consideration of strategic

issues for monitoring Section 5 provides guidance on monitoring according to the type of disposal

facility (geological near surface and facilities for mining and milling waste) Section 6 addresses

monitoring according to the stage of facility development Section 7 provides specific guidance for

surveillance activities only Finally Section 8 is concerned with the use of monitoring and surveillance

information in regard to compliance aspects and development and improvement of the safety case and

Section 9 provides a brief discussion of the salient issues pertaining to the management system for a

disposal facility

5

2 OVERVIEW OF MONITORING AND SURVEILLANCE

21 The BSS [8] defines lsquomonitoringrsquo (of public exposure) to be

ldquoThe measurement of dose or contamination for reasons related to the assessment or

control of exposure to radiation or radioactive substances and the interpretation of the

resultsrdquo

22 The IAEA Safety Guide on environmental and source monitoring [9] defines the terms lsquosource

monitoringrsquo and lsquoenvironmental monitoringrsquo as

a ldquoSource monitoring The measurement of activity in radioactive materials being

released to the environment or of external dose rates due to sources within a facility or

activityrdquo

b ldquoEnvironmental monitoring The measurement of external dose rates due to sources in

the environment or of radionuclide concentrations in environmental mediardquo

23 In the context of this Safety Guide the term monitoring refers to

Continuous or periodic observations and measurements of environmental engineering or

radiological parameters to help evaluate the behaviour of components of the waste

disposal system or of the impacts of the waste disposal system and its operation on the

public and the environment

24 Monitoring involves many characterization activities Information may have to be collected

over a period of time for a number of characterization tasks (eg groundwater flow rates moisture

content of soils daily precipitation) For other types of information once the parameter has been

defined there may be no need to continue with the sampling and measurement since it is not expected

to change in time or with development and closure of the facility (eg rock porosity)

25 Monitoring is needed to evaluate processes or parameters that are influential in the

development of the safety case The duration and frequency of monitoring may be determined by

regulatory requirements by the time scale of natural variations in a process or parameter by possible

changes associated with the construction and operation of the facility The need to address public

concern should also be considered in defining the monitoring programme

26 A programme for the surveillance of the facility should be established and implemented as

necessary and feasible It should consist of planned activities carried out to verify that the facility is

operating within the design limits and conditions and to detect any deterioration of structures systems

and components that could result in unsafe conditions [17] In the context of this Safety Guide the

term surveillance refers to

6

The physical inspection of a waste management facility in order to verify its integrity to

protect and preserve the passive safety barriers

27 Some countries do not differentiate between monitoring and surveillance of disposal facilities

28 In this respect the function of surveillance is to contribute to the detection of changes in the

engineering structures and systems of the disposal facility which might affect the radiological

performance of the system The relevant and expected changes can be identified by the post closure

safety assessment The surveillance programme is usually implemented through regular inspections of

the critical components of the waste disposal facility

29 Generally there is a need to collect site-specific data although some relevant monitoring data

may be available from other sources Safety cases are usually supported by data from a number of

sources which includes site-specific measurements regional data and generic information

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES

210 Requirement 21 of the Safety Requirements on the Disposal of Radioactive Waste [4] states

that ldquoA programme of monitoring shall be carried out prior to and during the construction and

operation of a disposal facility and after its closure if this is part of the safety case This programme

shall be designed to collect and update information necessary for the purposes of protection and safety

Information shall be obtained to confirm the conditions necessary for the safety of workers and

members of the public and protection of the environment during the period of operation of the facility

Monitoring shall also be carried out to confirm the absence of any conditions that could affect the

safety of the facility after closurerdquo

211 In addition Requirement 10 of Ref [4] indicates that ldquoAn appropriate level of surveillance and

control shall be applied to protect and preserve the passive safety features to the extent that this is

necessary so that they can fulfil the functions that they are assigned in the safety case for safety after

closurerdquo

212 Monitoring and surveillance programmes begin at site characterization phase of disposal

facility development and continue to evolve through to the post-closure period depending on the type

of the disposal facility The data collected and insights derived from monitoring should be integrated

into and inform planning decisions made throughout the life-cycle of a disposal facility As a result

provision should be made to anticipate the needs of monitoring at later periods of the facility lifetime

and to gather monitoring data that informs later planning and actions

213 Monitoring and surveillance of disposal facilities for radioactive waste has four broad

objectives

7

1 To demonstrate compliance with the regulatory constraints and licence conditions

2 To verify that the disposal system is functioning as expected This means that the components

fulfil their function as identified in the safety case and that actual conditions are consistent

with the assumptions made for post-closure safety

3 To strengthen understanding of aspects of system behaviour used in developing the safety case

for the dispoal facility and to allow further testing of models predicting those aspects

4 To accumulate an environmental database of the site the disposal facility and its surroundings

for future decisions that are part of a stepwise programme of construction operation and

closure of the disposal facility

214 As mentioned in Ref [4] ldquoMonitoring programmes are designed and implemented so as not to

reduce the overall level of safety of the facility after closurerdquo (para 54) ldquoTo some extent the safety of

a disposal facility can depend on some future actions such as maintenance work or surveillance

However this dependence has to be minimized to the extent possiblerdquo (para 322) ldquoFor a geological

disposal facility it is possible to provide for safety after closure by means of passive features In the

case of a near surface disposal facility actions such as maintenance monitoring or surveillance may

be necessary for a period of time after closure to ensure safetyrdquo (para 323)

215 The monitoring programme should be closely tied to the safety case Even if safety should not

rely on monitoring and surveillance the results of such a programme should be used to strengthen the

safety case and build confidence in safety As well information needs of the safety case should be

used to improve the monitoring program

216 Requirement 7 of Ref [4] indicates that ldquoThe host environment shall be selected the

engineered barriers of the disposal facility shall be designed and the facility shall be operated to ensure

that safety is provided by means of multiple safety functions Containment and isolation of the waste

shall be provided by means of a number of physical barriers of the disposal systemrdquo The monitoring

and surveillance programme should provide to the extent practical the necessary information to

ensure that each barrier and its associated safety function(s) performs as planned and indicated in the

safety case In addition the monitoring and surveillance programme should confirm that the

performances of the engineered and natural barriers are not damaged by the operational activities

217 Further to its technical objectives a monitoring and surveillance programme can be a suitable

tool for public reassurance In that sense consideration of public interest and interested parties

concerns may provide useful information to improve the monitoring programme by including social

aspects

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 8: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

CONTENTS

1 INTRODUCTION 11

BACKGROUND 11

OBJECTIVE 33

SCOPE 33

STRUCTURE 44

2 OVERVIEW OF MONITORING AND SURVEILLANCE 55

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES 66

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY REGARDING

MONITORING AND SURVEILLANCE PROGRAMMES 99

RESPONSIBILITIES OF THE OPERATOR 99

RESPONSIBILITIES OF THE REGULATORY BODY 99

4 DESIGN OF A MONITORING PROGRAMME 1313

5 MONITORING BY TYPE OF DISPOSAL FACILITY 1919

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME 2121

MONITORING FOR EMERGENCY RESPONSE 2424

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE

PROGRAMME 2727

TYPE AND FREQUENCY OF INSPECTIONS 2828

8 USE OF MONITORING AND SURVEILLANCE INFORMATION 3131

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES 3131

DEVIATIONS FROM EXPECTED RESULTS 3333

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE

PROGRAMME 3434

9 MANAGEMENT SYSTEM 3535

ANNEX I 3939

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION

COLLECTED FOR A GEOLOGICAL DISPOSAL PROGRAMME 3939

ANNEX II 5151

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FOR A NEAR SURFACE

DISPOSAL PROGRAMME 5151

1

1 INTRODUCTION

BACKGROUND

11 Radioactive waste arises from the generation of electricity in nuclear power plants from

nuclear fuel cycle operations and from other activities in the nuclear fuel cycle such as mining and

milling of uranium and thorium ores Radioactive waste also arises in a wide range of industrial and

medical activities It also arises from activities and processes in which radioactive materials of natural

origin become concentrated in waste material and safety needs to be considered in its management

12 A monitoring and surveillance programme is an important element in providing reassurance

that a disposal facility for radioactive waste provides the required level of safety during its operational

period and post-closure period depending on the type of the disposal The safety principles to be

applied in all radioactive waste management activities are set out in the IAEA Fundamental Safety

Principles [1] Within the safety standards series the safety requirements for Near Surface Disposal of

Radioactive Waste [2] and Geological Disposal of Radioactive Waste [3] providing specific

monitoring requirements for their respective types of facilities have been combined to create a single

safety standard for Disposal of Radioactive Waste [4]

13 The IAEA is also developing a Safety Guide on geological disposal facilities for radioactive

waste [5] and is preparing a Safety Guide on near surface disposal facilities for radioactive wastes [6]

as well as a Safety Guide on the protection of the public against exposure to natural sources of

radiation including NORM residues [7] The present Safety Guide provides support for these safety

standards in the area of monitoring and surveillance

14 Differing kinds of monitoring activities occur in each period of the lifetime of a radioactive

waste disposal facility This Safety Guide covers monitoring and surveillance during pre-operational

operational and post-closure periods for near surface geological and mine waste disposal facilities

These periods are defined as follows [4]

minus The pre-operational period includes concept definition site evaluation (selection

verification and confirmation) safety assessment and design studies It also includes the

development of those aspects of the safety case for safety in operation and after closure

that are required in order to set the conditions of authorization to obtain the authorization

and to proceed with the construction of the disposal facility and the initial operational

activities The monitoring and testing programmes that are needed to inform operational

management decisions are put in place

minus The operational period begins when waste is first received at the facility From this time

radiation exposures may occur as a result of waste management activities and these are

subject to control in accordance with the requirements for protection and safety

2

Monitoring surveillance and testing programmes continue to inform operational

management decisions and to provide the basis for decisions concerning the closure of

the facility or parts of it Safety assessments for the period of operation and after closure

and the safety case are updated as necessary to reflect actual experience and increasing

knowledge In the operational period construction activities may take place at the same

time as waste emplacement in and closure of other parts of the facility This period may

include activities for waste retrieval mdash if considered necessary mdash prior to closure

activities following the completion of waste emplacement and the final closure and

sealing of the facility

minus The post-closure period begins at the time when all the engineered containment and

isolation features have been put in place operational buildings and supporting services

have been decommissioned and the facility is in its final configuration After its closure

the safety of the disposal facility is provided for by means of passive features inherent in

the characteristics of the site and the facility and characteristics of the waste packages

together with certain institutional controls particularly for near surface facilities Such

institutional controls are put in place to prevent intrusion into facilities and to confirm

that the disposal system is performing as expected by means of monitoring and

surveillance Monitoring may also be carried out to provide public assurance The licence

will be terminated after the period of active institutional control when all the necessary

technical legal and financial requirements have been fulfilled

15 The International Basic Safety Standards for Protection against Ionizing Radiation and for the

Safety of Radiation Sources (the BSS) [8] and the IAEA Safety Guide for environmental and source

monitoring for purposes of radiation protection Ref [9] provide a framework for all generic aspects of

radiological monitoring In particular Ref [8] establishes the basic requirements for radiological

monitoring of public exposure and Ref [9] covers pre-operational monitoring operational monitoring

(including decommissioning) and post-closure radiological monitoring It also acknowledges the need

for monitoring a variety of non-radiological variables The present Safety Guide is intended to

elaborate upon the requirements in the BSS and to complement the guidance provided in Ref [9] in

particular in regard to performance monitoring aspects of disposal facility development On matters

pertaining to source and environmental monitoring the present Safety Guide is subsidiary to and

defers to Ref [9]

16 The draft International Basic Safety Standards currently under development to supersede Ref

[8] will contain an updated and extended set of requirements on the regulatory control and monitoring

of public exposure and safety of the radioactive waste management

17 There are presently four IAEA publications concerned with monitoring and surveillance of

disposal facilities Safety Reports Series No 27 on Monitoring and Surveillance of Residues from the

3

Mining and Milling of Uranium and Thorium [10] Safety Reports Series No 35 on Surveillance and

Monitoring of Near Surface Disposal Facilities for Radioactive Waste [11] Safety Reports Series No

64 on Programmes and Systems for Source and Environmental Radiation Monitoring [18] and IAEA-

TECDOC-1208 on Monitoring of Geological Repositories for High Level Radioactive Waste [12]

These publications have served as resources for development of the present Safety Guide

OBJECTIVE

18 The objective of this Safety Guide is to provide guidance for monitoring and surveillance of

radioactive waste disposal facilities during their entire lifetime The Safety Guide includes the

different objectives that monitoring has at the lifetime periods from initiation of work on a candidate

site to the period after closure of the disposal facility

SCOPE

19 This Safety Guide considers the monitoring and surveillance of three types of disposal

facilities

bull Near surface disposal facilities

bull Geological disposal facilities

bull Disposal facilities for uranium and thorium mine waste

The three types of disposal facilities listed above are considered to cover all the disposal options as

identified in the Safety Requirements on Disposal of Radioactive Waste [4] In this Safety Guide

borehole disposal facilities are not specifically addressed However borehole disposal is not

conceptually different from either near surface disposal or geological disposal of radioactive waste A

possible surveillance and monitoring programme suitable for a small scale borehole disposal facility is

discussed in other IAEA Safety Standards [20]

110 As explained in Ref [14] the term near surface disposal refers generally to disposal at or

within a few tens of metres of the ground surface The term geological disposal generally refers to

disposal in deep stable geological formations usually several hundred meters or more below the

surface Mining waste disposal facilities cover a spectrum of designs from above-grade mounds to

geological disposal of tailings slimes sometimes used as backfill in old mine workings The type of

disposal is controlled by the waste characteristics and in any case the suitability of waste for disposal

in a particular disposal facility is required to be demonstrated by the safety case and supporting safety

assessment for the facility From the safety point of view disposal depth is one of the factors

considered in assessing the safety of disposal the geological environment the waste characteristics

4

and engineered features are of equal or more importance than depth of disposal in assessing the safety

of disposal facility

111 This Safety Guide places emphasis on an approach to monitoring and surveillance that

provides data needed for the development of the safety case The safety case includes information

needed for siting construct operate and close the facility for supporting decisions on managing the

disposal programme as well as information that are of particular interest to interested parties [4]

Technical details on monitoring and surveillance methodologies are beyond the scope of this Safety

Guide however Refs [10 11 12 18] direct the reader to such information and Annexes I and II give

examples of monitoring programmes for geological and near surface disposal programmes

112 This Safety Guide does not specifically address monitoring that will be required for

bull Operating personnel

bull Waste characterization or tracking

bull Nuclear materials control in the case of facilities that will contain significant quantities of

nuclear materials

Nor does it focus on monitoring for non-radiological contaminants that may be of potential concern

Facility operators however should consider such contaminants when designing their monitoring

programme

113 This Safety Guide does not address monitoring for occupational exposure rather the focus is

on monitoring for disposal system performance and radiation protection of the public and the

environment Monitoring for occupational radiation protection is discussed in other IAEA safety

standards [13]

STRUCTURE

114 Section 2 provides an overview of monitoring and surveillance for radioactive waste disposal

facilities and describes overall objectives for a monitoring and surveillance programme Section 3

addresses roles and responsibilities of the regulatory body and the implementing organizations with

regard to monitoring and surveillance Sections 4 5 and 6 focus on monitoring More specifically

Section 4 addresses design of a monitoring programme and includes some consideration of strategic

issues for monitoring Section 5 provides guidance on monitoring according to the type of disposal

facility (geological near surface and facilities for mining and milling waste) Section 6 addresses

monitoring according to the stage of facility development Section 7 provides specific guidance for

surveillance activities only Finally Section 8 is concerned with the use of monitoring and surveillance

information in regard to compliance aspects and development and improvement of the safety case and

Section 9 provides a brief discussion of the salient issues pertaining to the management system for a

disposal facility

5

2 OVERVIEW OF MONITORING AND SURVEILLANCE

21 The BSS [8] defines lsquomonitoringrsquo (of public exposure) to be

ldquoThe measurement of dose or contamination for reasons related to the assessment or

control of exposure to radiation or radioactive substances and the interpretation of the

resultsrdquo

22 The IAEA Safety Guide on environmental and source monitoring [9] defines the terms lsquosource

monitoringrsquo and lsquoenvironmental monitoringrsquo as

a ldquoSource monitoring The measurement of activity in radioactive materials being

released to the environment or of external dose rates due to sources within a facility or

activityrdquo

b ldquoEnvironmental monitoring The measurement of external dose rates due to sources in

the environment or of radionuclide concentrations in environmental mediardquo

23 In the context of this Safety Guide the term monitoring refers to

Continuous or periodic observations and measurements of environmental engineering or

radiological parameters to help evaluate the behaviour of components of the waste

disposal system or of the impacts of the waste disposal system and its operation on the

public and the environment

24 Monitoring involves many characterization activities Information may have to be collected

over a period of time for a number of characterization tasks (eg groundwater flow rates moisture

content of soils daily precipitation) For other types of information once the parameter has been

defined there may be no need to continue with the sampling and measurement since it is not expected

to change in time or with development and closure of the facility (eg rock porosity)

25 Monitoring is needed to evaluate processes or parameters that are influential in the

development of the safety case The duration and frequency of monitoring may be determined by

regulatory requirements by the time scale of natural variations in a process or parameter by possible

changes associated with the construction and operation of the facility The need to address public

concern should also be considered in defining the monitoring programme

26 A programme for the surveillance of the facility should be established and implemented as

necessary and feasible It should consist of planned activities carried out to verify that the facility is

operating within the design limits and conditions and to detect any deterioration of structures systems

and components that could result in unsafe conditions [17] In the context of this Safety Guide the

term surveillance refers to

6

The physical inspection of a waste management facility in order to verify its integrity to

protect and preserve the passive safety barriers

27 Some countries do not differentiate between monitoring and surveillance of disposal facilities

28 In this respect the function of surveillance is to contribute to the detection of changes in the

engineering structures and systems of the disposal facility which might affect the radiological

performance of the system The relevant and expected changes can be identified by the post closure

safety assessment The surveillance programme is usually implemented through regular inspections of

the critical components of the waste disposal facility

29 Generally there is a need to collect site-specific data although some relevant monitoring data

may be available from other sources Safety cases are usually supported by data from a number of

sources which includes site-specific measurements regional data and generic information

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES

210 Requirement 21 of the Safety Requirements on the Disposal of Radioactive Waste [4] states

that ldquoA programme of monitoring shall be carried out prior to and during the construction and

operation of a disposal facility and after its closure if this is part of the safety case This programme

shall be designed to collect and update information necessary for the purposes of protection and safety

Information shall be obtained to confirm the conditions necessary for the safety of workers and

members of the public and protection of the environment during the period of operation of the facility

Monitoring shall also be carried out to confirm the absence of any conditions that could affect the

safety of the facility after closurerdquo

211 In addition Requirement 10 of Ref [4] indicates that ldquoAn appropriate level of surveillance and

control shall be applied to protect and preserve the passive safety features to the extent that this is

necessary so that they can fulfil the functions that they are assigned in the safety case for safety after

closurerdquo

212 Monitoring and surveillance programmes begin at site characterization phase of disposal

facility development and continue to evolve through to the post-closure period depending on the type

of the disposal facility The data collected and insights derived from monitoring should be integrated

into and inform planning decisions made throughout the life-cycle of a disposal facility As a result

provision should be made to anticipate the needs of monitoring at later periods of the facility lifetime

and to gather monitoring data that informs later planning and actions

213 Monitoring and surveillance of disposal facilities for radioactive waste has four broad

objectives

7

1 To demonstrate compliance with the regulatory constraints and licence conditions

2 To verify that the disposal system is functioning as expected This means that the components

fulfil their function as identified in the safety case and that actual conditions are consistent

with the assumptions made for post-closure safety

3 To strengthen understanding of aspects of system behaviour used in developing the safety case

for the dispoal facility and to allow further testing of models predicting those aspects

4 To accumulate an environmental database of the site the disposal facility and its surroundings

for future decisions that are part of a stepwise programme of construction operation and

closure of the disposal facility

214 As mentioned in Ref [4] ldquoMonitoring programmes are designed and implemented so as not to

reduce the overall level of safety of the facility after closurerdquo (para 54) ldquoTo some extent the safety of

a disposal facility can depend on some future actions such as maintenance work or surveillance

However this dependence has to be minimized to the extent possiblerdquo (para 322) ldquoFor a geological

disposal facility it is possible to provide for safety after closure by means of passive features In the

case of a near surface disposal facility actions such as maintenance monitoring or surveillance may

be necessary for a period of time after closure to ensure safetyrdquo (para 323)

215 The monitoring programme should be closely tied to the safety case Even if safety should not

rely on monitoring and surveillance the results of such a programme should be used to strengthen the

safety case and build confidence in safety As well information needs of the safety case should be

used to improve the monitoring program

216 Requirement 7 of Ref [4] indicates that ldquoThe host environment shall be selected the

engineered barriers of the disposal facility shall be designed and the facility shall be operated to ensure

that safety is provided by means of multiple safety functions Containment and isolation of the waste

shall be provided by means of a number of physical barriers of the disposal systemrdquo The monitoring

and surveillance programme should provide to the extent practical the necessary information to

ensure that each barrier and its associated safety function(s) performs as planned and indicated in the

safety case In addition the monitoring and surveillance programme should confirm that the

performances of the engineered and natural barriers are not damaged by the operational activities

217 Further to its technical objectives a monitoring and surveillance programme can be a suitable

tool for public reassurance In that sense consideration of public interest and interested parties

concerns may provide useful information to improve the monitoring programme by including social

aspects

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 9: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FOR A NEAR SURFACE

DISPOSAL PROGRAMME 5151

1

1 INTRODUCTION

BACKGROUND

11 Radioactive waste arises from the generation of electricity in nuclear power plants from

nuclear fuel cycle operations and from other activities in the nuclear fuel cycle such as mining and

milling of uranium and thorium ores Radioactive waste also arises in a wide range of industrial and

medical activities It also arises from activities and processes in which radioactive materials of natural

origin become concentrated in waste material and safety needs to be considered in its management

12 A monitoring and surveillance programme is an important element in providing reassurance

that a disposal facility for radioactive waste provides the required level of safety during its operational

period and post-closure period depending on the type of the disposal The safety principles to be

applied in all radioactive waste management activities are set out in the IAEA Fundamental Safety

Principles [1] Within the safety standards series the safety requirements for Near Surface Disposal of

Radioactive Waste [2] and Geological Disposal of Radioactive Waste [3] providing specific

monitoring requirements for their respective types of facilities have been combined to create a single

safety standard for Disposal of Radioactive Waste [4]

13 The IAEA is also developing a Safety Guide on geological disposal facilities for radioactive

waste [5] and is preparing a Safety Guide on near surface disposal facilities for radioactive wastes [6]

as well as a Safety Guide on the protection of the public against exposure to natural sources of

radiation including NORM residues [7] The present Safety Guide provides support for these safety

standards in the area of monitoring and surveillance

14 Differing kinds of monitoring activities occur in each period of the lifetime of a radioactive

waste disposal facility This Safety Guide covers monitoring and surveillance during pre-operational

operational and post-closure periods for near surface geological and mine waste disposal facilities

These periods are defined as follows [4]

minus The pre-operational period includes concept definition site evaluation (selection

verification and confirmation) safety assessment and design studies It also includes the

development of those aspects of the safety case for safety in operation and after closure

that are required in order to set the conditions of authorization to obtain the authorization

and to proceed with the construction of the disposal facility and the initial operational

activities The monitoring and testing programmes that are needed to inform operational

management decisions are put in place

minus The operational period begins when waste is first received at the facility From this time

radiation exposures may occur as a result of waste management activities and these are

subject to control in accordance with the requirements for protection and safety

2

Monitoring surveillance and testing programmes continue to inform operational

management decisions and to provide the basis for decisions concerning the closure of

the facility or parts of it Safety assessments for the period of operation and after closure

and the safety case are updated as necessary to reflect actual experience and increasing

knowledge In the operational period construction activities may take place at the same

time as waste emplacement in and closure of other parts of the facility This period may

include activities for waste retrieval mdash if considered necessary mdash prior to closure

activities following the completion of waste emplacement and the final closure and

sealing of the facility

minus The post-closure period begins at the time when all the engineered containment and

isolation features have been put in place operational buildings and supporting services

have been decommissioned and the facility is in its final configuration After its closure

the safety of the disposal facility is provided for by means of passive features inherent in

the characteristics of the site and the facility and characteristics of the waste packages

together with certain institutional controls particularly for near surface facilities Such

institutional controls are put in place to prevent intrusion into facilities and to confirm

that the disposal system is performing as expected by means of monitoring and

surveillance Monitoring may also be carried out to provide public assurance The licence

will be terminated after the period of active institutional control when all the necessary

technical legal and financial requirements have been fulfilled

15 The International Basic Safety Standards for Protection against Ionizing Radiation and for the

Safety of Radiation Sources (the BSS) [8] and the IAEA Safety Guide for environmental and source

monitoring for purposes of radiation protection Ref [9] provide a framework for all generic aspects of

radiological monitoring In particular Ref [8] establishes the basic requirements for radiological

monitoring of public exposure and Ref [9] covers pre-operational monitoring operational monitoring

(including decommissioning) and post-closure radiological monitoring It also acknowledges the need

for monitoring a variety of non-radiological variables The present Safety Guide is intended to

elaborate upon the requirements in the BSS and to complement the guidance provided in Ref [9] in

particular in regard to performance monitoring aspects of disposal facility development On matters

pertaining to source and environmental monitoring the present Safety Guide is subsidiary to and

defers to Ref [9]

16 The draft International Basic Safety Standards currently under development to supersede Ref

[8] will contain an updated and extended set of requirements on the regulatory control and monitoring

of public exposure and safety of the radioactive waste management

17 There are presently four IAEA publications concerned with monitoring and surveillance of

disposal facilities Safety Reports Series No 27 on Monitoring and Surveillance of Residues from the

3

Mining and Milling of Uranium and Thorium [10] Safety Reports Series No 35 on Surveillance and

Monitoring of Near Surface Disposal Facilities for Radioactive Waste [11] Safety Reports Series No

64 on Programmes and Systems for Source and Environmental Radiation Monitoring [18] and IAEA-

TECDOC-1208 on Monitoring of Geological Repositories for High Level Radioactive Waste [12]

These publications have served as resources for development of the present Safety Guide

OBJECTIVE

18 The objective of this Safety Guide is to provide guidance for monitoring and surveillance of

radioactive waste disposal facilities during their entire lifetime The Safety Guide includes the

different objectives that monitoring has at the lifetime periods from initiation of work on a candidate

site to the period after closure of the disposal facility

SCOPE

19 This Safety Guide considers the monitoring and surveillance of three types of disposal

facilities

bull Near surface disposal facilities

bull Geological disposal facilities

bull Disposal facilities for uranium and thorium mine waste

The three types of disposal facilities listed above are considered to cover all the disposal options as

identified in the Safety Requirements on Disposal of Radioactive Waste [4] In this Safety Guide

borehole disposal facilities are not specifically addressed However borehole disposal is not

conceptually different from either near surface disposal or geological disposal of radioactive waste A

possible surveillance and monitoring programme suitable for a small scale borehole disposal facility is

discussed in other IAEA Safety Standards [20]

110 As explained in Ref [14] the term near surface disposal refers generally to disposal at or

within a few tens of metres of the ground surface The term geological disposal generally refers to

disposal in deep stable geological formations usually several hundred meters or more below the

surface Mining waste disposal facilities cover a spectrum of designs from above-grade mounds to

geological disposal of tailings slimes sometimes used as backfill in old mine workings The type of

disposal is controlled by the waste characteristics and in any case the suitability of waste for disposal

in a particular disposal facility is required to be demonstrated by the safety case and supporting safety

assessment for the facility From the safety point of view disposal depth is one of the factors

considered in assessing the safety of disposal the geological environment the waste characteristics

4

and engineered features are of equal or more importance than depth of disposal in assessing the safety

of disposal facility

111 This Safety Guide places emphasis on an approach to monitoring and surveillance that

provides data needed for the development of the safety case The safety case includes information

needed for siting construct operate and close the facility for supporting decisions on managing the

disposal programme as well as information that are of particular interest to interested parties [4]

Technical details on monitoring and surveillance methodologies are beyond the scope of this Safety

Guide however Refs [10 11 12 18] direct the reader to such information and Annexes I and II give

examples of monitoring programmes for geological and near surface disposal programmes

112 This Safety Guide does not specifically address monitoring that will be required for

bull Operating personnel

bull Waste characterization or tracking

bull Nuclear materials control in the case of facilities that will contain significant quantities of

nuclear materials

Nor does it focus on monitoring for non-radiological contaminants that may be of potential concern

Facility operators however should consider such contaminants when designing their monitoring

programme

113 This Safety Guide does not address monitoring for occupational exposure rather the focus is

on monitoring for disposal system performance and radiation protection of the public and the

environment Monitoring for occupational radiation protection is discussed in other IAEA safety

standards [13]

STRUCTURE

114 Section 2 provides an overview of monitoring and surveillance for radioactive waste disposal

facilities and describes overall objectives for a monitoring and surveillance programme Section 3

addresses roles and responsibilities of the regulatory body and the implementing organizations with

regard to monitoring and surveillance Sections 4 5 and 6 focus on monitoring More specifically

Section 4 addresses design of a monitoring programme and includes some consideration of strategic

issues for monitoring Section 5 provides guidance on monitoring according to the type of disposal

facility (geological near surface and facilities for mining and milling waste) Section 6 addresses

monitoring according to the stage of facility development Section 7 provides specific guidance for

surveillance activities only Finally Section 8 is concerned with the use of monitoring and surveillance

information in regard to compliance aspects and development and improvement of the safety case and

Section 9 provides a brief discussion of the salient issues pertaining to the management system for a

disposal facility

5

2 OVERVIEW OF MONITORING AND SURVEILLANCE

21 The BSS [8] defines lsquomonitoringrsquo (of public exposure) to be

ldquoThe measurement of dose or contamination for reasons related to the assessment or

control of exposure to radiation or radioactive substances and the interpretation of the

resultsrdquo

22 The IAEA Safety Guide on environmental and source monitoring [9] defines the terms lsquosource

monitoringrsquo and lsquoenvironmental monitoringrsquo as

a ldquoSource monitoring The measurement of activity in radioactive materials being

released to the environment or of external dose rates due to sources within a facility or

activityrdquo

b ldquoEnvironmental monitoring The measurement of external dose rates due to sources in

the environment or of radionuclide concentrations in environmental mediardquo

23 In the context of this Safety Guide the term monitoring refers to

Continuous or periodic observations and measurements of environmental engineering or

radiological parameters to help evaluate the behaviour of components of the waste

disposal system or of the impacts of the waste disposal system and its operation on the

public and the environment

24 Monitoring involves many characterization activities Information may have to be collected

over a period of time for a number of characterization tasks (eg groundwater flow rates moisture

content of soils daily precipitation) For other types of information once the parameter has been

defined there may be no need to continue with the sampling and measurement since it is not expected

to change in time or with development and closure of the facility (eg rock porosity)

25 Monitoring is needed to evaluate processes or parameters that are influential in the

development of the safety case The duration and frequency of monitoring may be determined by

regulatory requirements by the time scale of natural variations in a process or parameter by possible

changes associated with the construction and operation of the facility The need to address public

concern should also be considered in defining the monitoring programme

26 A programme for the surveillance of the facility should be established and implemented as

necessary and feasible It should consist of planned activities carried out to verify that the facility is

operating within the design limits and conditions and to detect any deterioration of structures systems

and components that could result in unsafe conditions [17] In the context of this Safety Guide the

term surveillance refers to

6

The physical inspection of a waste management facility in order to verify its integrity to

protect and preserve the passive safety barriers

27 Some countries do not differentiate between monitoring and surveillance of disposal facilities

28 In this respect the function of surveillance is to contribute to the detection of changes in the

engineering structures and systems of the disposal facility which might affect the radiological

performance of the system The relevant and expected changes can be identified by the post closure

safety assessment The surveillance programme is usually implemented through regular inspections of

the critical components of the waste disposal facility

29 Generally there is a need to collect site-specific data although some relevant monitoring data

may be available from other sources Safety cases are usually supported by data from a number of

sources which includes site-specific measurements regional data and generic information

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES

210 Requirement 21 of the Safety Requirements on the Disposal of Radioactive Waste [4] states

that ldquoA programme of monitoring shall be carried out prior to and during the construction and

operation of a disposal facility and after its closure if this is part of the safety case This programme

shall be designed to collect and update information necessary for the purposes of protection and safety

Information shall be obtained to confirm the conditions necessary for the safety of workers and

members of the public and protection of the environment during the period of operation of the facility

Monitoring shall also be carried out to confirm the absence of any conditions that could affect the

safety of the facility after closurerdquo

211 In addition Requirement 10 of Ref [4] indicates that ldquoAn appropriate level of surveillance and

control shall be applied to protect and preserve the passive safety features to the extent that this is

necessary so that they can fulfil the functions that they are assigned in the safety case for safety after

closurerdquo

212 Monitoring and surveillance programmes begin at site characterization phase of disposal

facility development and continue to evolve through to the post-closure period depending on the type

of the disposal facility The data collected and insights derived from monitoring should be integrated

into and inform planning decisions made throughout the life-cycle of a disposal facility As a result

provision should be made to anticipate the needs of monitoring at later periods of the facility lifetime

and to gather monitoring data that informs later planning and actions

213 Monitoring and surveillance of disposal facilities for radioactive waste has four broad

objectives

7

1 To demonstrate compliance with the regulatory constraints and licence conditions

2 To verify that the disposal system is functioning as expected This means that the components

fulfil their function as identified in the safety case and that actual conditions are consistent

with the assumptions made for post-closure safety

3 To strengthen understanding of aspects of system behaviour used in developing the safety case

for the dispoal facility and to allow further testing of models predicting those aspects

4 To accumulate an environmental database of the site the disposal facility and its surroundings

for future decisions that are part of a stepwise programme of construction operation and

closure of the disposal facility

214 As mentioned in Ref [4] ldquoMonitoring programmes are designed and implemented so as not to

reduce the overall level of safety of the facility after closurerdquo (para 54) ldquoTo some extent the safety of

a disposal facility can depend on some future actions such as maintenance work or surveillance

However this dependence has to be minimized to the extent possiblerdquo (para 322) ldquoFor a geological

disposal facility it is possible to provide for safety after closure by means of passive features In the

case of a near surface disposal facility actions such as maintenance monitoring or surveillance may

be necessary for a period of time after closure to ensure safetyrdquo (para 323)

215 The monitoring programme should be closely tied to the safety case Even if safety should not

rely on monitoring and surveillance the results of such a programme should be used to strengthen the

safety case and build confidence in safety As well information needs of the safety case should be

used to improve the monitoring program

216 Requirement 7 of Ref [4] indicates that ldquoThe host environment shall be selected the

engineered barriers of the disposal facility shall be designed and the facility shall be operated to ensure

that safety is provided by means of multiple safety functions Containment and isolation of the waste

shall be provided by means of a number of physical barriers of the disposal systemrdquo The monitoring

and surveillance programme should provide to the extent practical the necessary information to

ensure that each barrier and its associated safety function(s) performs as planned and indicated in the

safety case In addition the monitoring and surveillance programme should confirm that the

performances of the engineered and natural barriers are not damaged by the operational activities

217 Further to its technical objectives a monitoring and surveillance programme can be a suitable

tool for public reassurance In that sense consideration of public interest and interested parties

concerns may provide useful information to improve the monitoring programme by including social

aspects

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 10: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

1

1 INTRODUCTION

BACKGROUND

11 Radioactive waste arises from the generation of electricity in nuclear power plants from

nuclear fuel cycle operations and from other activities in the nuclear fuel cycle such as mining and

milling of uranium and thorium ores Radioactive waste also arises in a wide range of industrial and

medical activities It also arises from activities and processes in which radioactive materials of natural

origin become concentrated in waste material and safety needs to be considered in its management

12 A monitoring and surveillance programme is an important element in providing reassurance

that a disposal facility for radioactive waste provides the required level of safety during its operational

period and post-closure period depending on the type of the disposal The safety principles to be

applied in all radioactive waste management activities are set out in the IAEA Fundamental Safety

Principles [1] Within the safety standards series the safety requirements for Near Surface Disposal of

Radioactive Waste [2] and Geological Disposal of Radioactive Waste [3] providing specific

monitoring requirements for their respective types of facilities have been combined to create a single

safety standard for Disposal of Radioactive Waste [4]

13 The IAEA is also developing a Safety Guide on geological disposal facilities for radioactive

waste [5] and is preparing a Safety Guide on near surface disposal facilities for radioactive wastes [6]

as well as a Safety Guide on the protection of the public against exposure to natural sources of

radiation including NORM residues [7] The present Safety Guide provides support for these safety

standards in the area of monitoring and surveillance

14 Differing kinds of monitoring activities occur in each period of the lifetime of a radioactive

waste disposal facility This Safety Guide covers monitoring and surveillance during pre-operational

operational and post-closure periods for near surface geological and mine waste disposal facilities

These periods are defined as follows [4]

minus The pre-operational period includes concept definition site evaluation (selection

verification and confirmation) safety assessment and design studies It also includes the

development of those aspects of the safety case for safety in operation and after closure

that are required in order to set the conditions of authorization to obtain the authorization

and to proceed with the construction of the disposal facility and the initial operational

activities The monitoring and testing programmes that are needed to inform operational

management decisions are put in place

minus The operational period begins when waste is first received at the facility From this time

radiation exposures may occur as a result of waste management activities and these are

subject to control in accordance with the requirements for protection and safety

2

Monitoring surveillance and testing programmes continue to inform operational

management decisions and to provide the basis for decisions concerning the closure of

the facility or parts of it Safety assessments for the period of operation and after closure

and the safety case are updated as necessary to reflect actual experience and increasing

knowledge In the operational period construction activities may take place at the same

time as waste emplacement in and closure of other parts of the facility This period may

include activities for waste retrieval mdash if considered necessary mdash prior to closure

activities following the completion of waste emplacement and the final closure and

sealing of the facility

minus The post-closure period begins at the time when all the engineered containment and

isolation features have been put in place operational buildings and supporting services

have been decommissioned and the facility is in its final configuration After its closure

the safety of the disposal facility is provided for by means of passive features inherent in

the characteristics of the site and the facility and characteristics of the waste packages

together with certain institutional controls particularly for near surface facilities Such

institutional controls are put in place to prevent intrusion into facilities and to confirm

that the disposal system is performing as expected by means of monitoring and

surveillance Monitoring may also be carried out to provide public assurance The licence

will be terminated after the period of active institutional control when all the necessary

technical legal and financial requirements have been fulfilled

15 The International Basic Safety Standards for Protection against Ionizing Radiation and for the

Safety of Radiation Sources (the BSS) [8] and the IAEA Safety Guide for environmental and source

monitoring for purposes of radiation protection Ref [9] provide a framework for all generic aspects of

radiological monitoring In particular Ref [8] establishes the basic requirements for radiological

monitoring of public exposure and Ref [9] covers pre-operational monitoring operational monitoring

(including decommissioning) and post-closure radiological monitoring It also acknowledges the need

for monitoring a variety of non-radiological variables The present Safety Guide is intended to

elaborate upon the requirements in the BSS and to complement the guidance provided in Ref [9] in

particular in regard to performance monitoring aspects of disposal facility development On matters

pertaining to source and environmental monitoring the present Safety Guide is subsidiary to and

defers to Ref [9]

16 The draft International Basic Safety Standards currently under development to supersede Ref

[8] will contain an updated and extended set of requirements on the regulatory control and monitoring

of public exposure and safety of the radioactive waste management

17 There are presently four IAEA publications concerned with monitoring and surveillance of

disposal facilities Safety Reports Series No 27 on Monitoring and Surveillance of Residues from the

3

Mining and Milling of Uranium and Thorium [10] Safety Reports Series No 35 on Surveillance and

Monitoring of Near Surface Disposal Facilities for Radioactive Waste [11] Safety Reports Series No

64 on Programmes and Systems for Source and Environmental Radiation Monitoring [18] and IAEA-

TECDOC-1208 on Monitoring of Geological Repositories for High Level Radioactive Waste [12]

These publications have served as resources for development of the present Safety Guide

OBJECTIVE

18 The objective of this Safety Guide is to provide guidance for monitoring and surveillance of

radioactive waste disposal facilities during their entire lifetime The Safety Guide includes the

different objectives that monitoring has at the lifetime periods from initiation of work on a candidate

site to the period after closure of the disposal facility

SCOPE

19 This Safety Guide considers the monitoring and surveillance of three types of disposal

facilities

bull Near surface disposal facilities

bull Geological disposal facilities

bull Disposal facilities for uranium and thorium mine waste

The three types of disposal facilities listed above are considered to cover all the disposal options as

identified in the Safety Requirements on Disposal of Radioactive Waste [4] In this Safety Guide

borehole disposal facilities are not specifically addressed However borehole disposal is not

conceptually different from either near surface disposal or geological disposal of radioactive waste A

possible surveillance and monitoring programme suitable for a small scale borehole disposal facility is

discussed in other IAEA Safety Standards [20]

110 As explained in Ref [14] the term near surface disposal refers generally to disposal at or

within a few tens of metres of the ground surface The term geological disposal generally refers to

disposal in deep stable geological formations usually several hundred meters or more below the

surface Mining waste disposal facilities cover a spectrum of designs from above-grade mounds to

geological disposal of tailings slimes sometimes used as backfill in old mine workings The type of

disposal is controlled by the waste characteristics and in any case the suitability of waste for disposal

in a particular disposal facility is required to be demonstrated by the safety case and supporting safety

assessment for the facility From the safety point of view disposal depth is one of the factors

considered in assessing the safety of disposal the geological environment the waste characteristics

4

and engineered features are of equal or more importance than depth of disposal in assessing the safety

of disposal facility

111 This Safety Guide places emphasis on an approach to monitoring and surveillance that

provides data needed for the development of the safety case The safety case includes information

needed for siting construct operate and close the facility for supporting decisions on managing the

disposal programme as well as information that are of particular interest to interested parties [4]

Technical details on monitoring and surveillance methodologies are beyond the scope of this Safety

Guide however Refs [10 11 12 18] direct the reader to such information and Annexes I and II give

examples of monitoring programmes for geological and near surface disposal programmes

112 This Safety Guide does not specifically address monitoring that will be required for

bull Operating personnel

bull Waste characterization or tracking

bull Nuclear materials control in the case of facilities that will contain significant quantities of

nuclear materials

Nor does it focus on monitoring for non-radiological contaminants that may be of potential concern

Facility operators however should consider such contaminants when designing their monitoring

programme

113 This Safety Guide does not address monitoring for occupational exposure rather the focus is

on monitoring for disposal system performance and radiation protection of the public and the

environment Monitoring for occupational radiation protection is discussed in other IAEA safety

standards [13]

STRUCTURE

114 Section 2 provides an overview of monitoring and surveillance for radioactive waste disposal

facilities and describes overall objectives for a monitoring and surveillance programme Section 3

addresses roles and responsibilities of the regulatory body and the implementing organizations with

regard to monitoring and surveillance Sections 4 5 and 6 focus on monitoring More specifically

Section 4 addresses design of a monitoring programme and includes some consideration of strategic

issues for monitoring Section 5 provides guidance on monitoring according to the type of disposal

facility (geological near surface and facilities for mining and milling waste) Section 6 addresses

monitoring according to the stage of facility development Section 7 provides specific guidance for

surveillance activities only Finally Section 8 is concerned with the use of monitoring and surveillance

information in regard to compliance aspects and development and improvement of the safety case and

Section 9 provides a brief discussion of the salient issues pertaining to the management system for a

disposal facility

5

2 OVERVIEW OF MONITORING AND SURVEILLANCE

21 The BSS [8] defines lsquomonitoringrsquo (of public exposure) to be

ldquoThe measurement of dose or contamination for reasons related to the assessment or

control of exposure to radiation or radioactive substances and the interpretation of the

resultsrdquo

22 The IAEA Safety Guide on environmental and source monitoring [9] defines the terms lsquosource

monitoringrsquo and lsquoenvironmental monitoringrsquo as

a ldquoSource monitoring The measurement of activity in radioactive materials being

released to the environment or of external dose rates due to sources within a facility or

activityrdquo

b ldquoEnvironmental monitoring The measurement of external dose rates due to sources in

the environment or of radionuclide concentrations in environmental mediardquo

23 In the context of this Safety Guide the term monitoring refers to

Continuous or periodic observations and measurements of environmental engineering or

radiological parameters to help evaluate the behaviour of components of the waste

disposal system or of the impacts of the waste disposal system and its operation on the

public and the environment

24 Monitoring involves many characterization activities Information may have to be collected

over a period of time for a number of characterization tasks (eg groundwater flow rates moisture

content of soils daily precipitation) For other types of information once the parameter has been

defined there may be no need to continue with the sampling and measurement since it is not expected

to change in time or with development and closure of the facility (eg rock porosity)

25 Monitoring is needed to evaluate processes or parameters that are influential in the

development of the safety case The duration and frequency of monitoring may be determined by

regulatory requirements by the time scale of natural variations in a process or parameter by possible

changes associated with the construction and operation of the facility The need to address public

concern should also be considered in defining the monitoring programme

26 A programme for the surveillance of the facility should be established and implemented as

necessary and feasible It should consist of planned activities carried out to verify that the facility is

operating within the design limits and conditions and to detect any deterioration of structures systems

and components that could result in unsafe conditions [17] In the context of this Safety Guide the

term surveillance refers to

6

The physical inspection of a waste management facility in order to verify its integrity to

protect and preserve the passive safety barriers

27 Some countries do not differentiate between monitoring and surveillance of disposal facilities

28 In this respect the function of surveillance is to contribute to the detection of changes in the

engineering structures and systems of the disposal facility which might affect the radiological

performance of the system The relevant and expected changes can be identified by the post closure

safety assessment The surveillance programme is usually implemented through regular inspections of

the critical components of the waste disposal facility

29 Generally there is a need to collect site-specific data although some relevant monitoring data

may be available from other sources Safety cases are usually supported by data from a number of

sources which includes site-specific measurements regional data and generic information

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES

210 Requirement 21 of the Safety Requirements on the Disposal of Radioactive Waste [4] states

that ldquoA programme of monitoring shall be carried out prior to and during the construction and

operation of a disposal facility and after its closure if this is part of the safety case This programme

shall be designed to collect and update information necessary for the purposes of protection and safety

Information shall be obtained to confirm the conditions necessary for the safety of workers and

members of the public and protection of the environment during the period of operation of the facility

Monitoring shall also be carried out to confirm the absence of any conditions that could affect the

safety of the facility after closurerdquo

211 In addition Requirement 10 of Ref [4] indicates that ldquoAn appropriate level of surveillance and

control shall be applied to protect and preserve the passive safety features to the extent that this is

necessary so that they can fulfil the functions that they are assigned in the safety case for safety after

closurerdquo

212 Monitoring and surveillance programmes begin at site characterization phase of disposal

facility development and continue to evolve through to the post-closure period depending on the type

of the disposal facility The data collected and insights derived from monitoring should be integrated

into and inform planning decisions made throughout the life-cycle of a disposal facility As a result

provision should be made to anticipate the needs of monitoring at later periods of the facility lifetime

and to gather monitoring data that informs later planning and actions

213 Monitoring and surveillance of disposal facilities for radioactive waste has four broad

objectives

7

1 To demonstrate compliance with the regulatory constraints and licence conditions

2 To verify that the disposal system is functioning as expected This means that the components

fulfil their function as identified in the safety case and that actual conditions are consistent

with the assumptions made for post-closure safety

3 To strengthen understanding of aspects of system behaviour used in developing the safety case

for the dispoal facility and to allow further testing of models predicting those aspects

4 To accumulate an environmental database of the site the disposal facility and its surroundings

for future decisions that are part of a stepwise programme of construction operation and

closure of the disposal facility

214 As mentioned in Ref [4] ldquoMonitoring programmes are designed and implemented so as not to

reduce the overall level of safety of the facility after closurerdquo (para 54) ldquoTo some extent the safety of

a disposal facility can depend on some future actions such as maintenance work or surveillance

However this dependence has to be minimized to the extent possiblerdquo (para 322) ldquoFor a geological

disposal facility it is possible to provide for safety after closure by means of passive features In the

case of a near surface disposal facility actions such as maintenance monitoring or surveillance may

be necessary for a period of time after closure to ensure safetyrdquo (para 323)

215 The monitoring programme should be closely tied to the safety case Even if safety should not

rely on monitoring and surveillance the results of such a programme should be used to strengthen the

safety case and build confidence in safety As well information needs of the safety case should be

used to improve the monitoring program

216 Requirement 7 of Ref [4] indicates that ldquoThe host environment shall be selected the

engineered barriers of the disposal facility shall be designed and the facility shall be operated to ensure

that safety is provided by means of multiple safety functions Containment and isolation of the waste

shall be provided by means of a number of physical barriers of the disposal systemrdquo The monitoring

and surveillance programme should provide to the extent practical the necessary information to

ensure that each barrier and its associated safety function(s) performs as planned and indicated in the

safety case In addition the monitoring and surveillance programme should confirm that the

performances of the engineered and natural barriers are not damaged by the operational activities

217 Further to its technical objectives a monitoring and surveillance programme can be a suitable

tool for public reassurance In that sense consideration of public interest and interested parties

concerns may provide useful information to improve the monitoring programme by including social

aspects

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 11: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

2

Monitoring surveillance and testing programmes continue to inform operational

management decisions and to provide the basis for decisions concerning the closure of

the facility or parts of it Safety assessments for the period of operation and after closure

and the safety case are updated as necessary to reflect actual experience and increasing

knowledge In the operational period construction activities may take place at the same

time as waste emplacement in and closure of other parts of the facility This period may

include activities for waste retrieval mdash if considered necessary mdash prior to closure

activities following the completion of waste emplacement and the final closure and

sealing of the facility

minus The post-closure period begins at the time when all the engineered containment and

isolation features have been put in place operational buildings and supporting services

have been decommissioned and the facility is in its final configuration After its closure

the safety of the disposal facility is provided for by means of passive features inherent in

the characteristics of the site and the facility and characteristics of the waste packages

together with certain institutional controls particularly for near surface facilities Such

institutional controls are put in place to prevent intrusion into facilities and to confirm

that the disposal system is performing as expected by means of monitoring and

surveillance Monitoring may also be carried out to provide public assurance The licence

will be terminated after the period of active institutional control when all the necessary

technical legal and financial requirements have been fulfilled

15 The International Basic Safety Standards for Protection against Ionizing Radiation and for the

Safety of Radiation Sources (the BSS) [8] and the IAEA Safety Guide for environmental and source

monitoring for purposes of radiation protection Ref [9] provide a framework for all generic aspects of

radiological monitoring In particular Ref [8] establishes the basic requirements for radiological

monitoring of public exposure and Ref [9] covers pre-operational monitoring operational monitoring

(including decommissioning) and post-closure radiological monitoring It also acknowledges the need

for monitoring a variety of non-radiological variables The present Safety Guide is intended to

elaborate upon the requirements in the BSS and to complement the guidance provided in Ref [9] in

particular in regard to performance monitoring aspects of disposal facility development On matters

pertaining to source and environmental monitoring the present Safety Guide is subsidiary to and

defers to Ref [9]

16 The draft International Basic Safety Standards currently under development to supersede Ref

[8] will contain an updated and extended set of requirements on the regulatory control and monitoring

of public exposure and safety of the radioactive waste management

17 There are presently four IAEA publications concerned with monitoring and surveillance of

disposal facilities Safety Reports Series No 27 on Monitoring and Surveillance of Residues from the

3

Mining and Milling of Uranium and Thorium [10] Safety Reports Series No 35 on Surveillance and

Monitoring of Near Surface Disposal Facilities for Radioactive Waste [11] Safety Reports Series No

64 on Programmes and Systems for Source and Environmental Radiation Monitoring [18] and IAEA-

TECDOC-1208 on Monitoring of Geological Repositories for High Level Radioactive Waste [12]

These publications have served as resources for development of the present Safety Guide

OBJECTIVE

18 The objective of this Safety Guide is to provide guidance for monitoring and surveillance of

radioactive waste disposal facilities during their entire lifetime The Safety Guide includes the

different objectives that monitoring has at the lifetime periods from initiation of work on a candidate

site to the period after closure of the disposal facility

SCOPE

19 This Safety Guide considers the monitoring and surveillance of three types of disposal

facilities

bull Near surface disposal facilities

bull Geological disposal facilities

bull Disposal facilities for uranium and thorium mine waste

The three types of disposal facilities listed above are considered to cover all the disposal options as

identified in the Safety Requirements on Disposal of Radioactive Waste [4] In this Safety Guide

borehole disposal facilities are not specifically addressed However borehole disposal is not

conceptually different from either near surface disposal or geological disposal of radioactive waste A

possible surveillance and monitoring programme suitable for a small scale borehole disposal facility is

discussed in other IAEA Safety Standards [20]

110 As explained in Ref [14] the term near surface disposal refers generally to disposal at or

within a few tens of metres of the ground surface The term geological disposal generally refers to

disposal in deep stable geological formations usually several hundred meters or more below the

surface Mining waste disposal facilities cover a spectrum of designs from above-grade mounds to

geological disposal of tailings slimes sometimes used as backfill in old mine workings The type of

disposal is controlled by the waste characteristics and in any case the suitability of waste for disposal

in a particular disposal facility is required to be demonstrated by the safety case and supporting safety

assessment for the facility From the safety point of view disposal depth is one of the factors

considered in assessing the safety of disposal the geological environment the waste characteristics

4

and engineered features are of equal or more importance than depth of disposal in assessing the safety

of disposal facility

111 This Safety Guide places emphasis on an approach to monitoring and surveillance that

provides data needed for the development of the safety case The safety case includes information

needed for siting construct operate and close the facility for supporting decisions on managing the

disposal programme as well as information that are of particular interest to interested parties [4]

Technical details on monitoring and surveillance methodologies are beyond the scope of this Safety

Guide however Refs [10 11 12 18] direct the reader to such information and Annexes I and II give

examples of monitoring programmes for geological and near surface disposal programmes

112 This Safety Guide does not specifically address monitoring that will be required for

bull Operating personnel

bull Waste characterization or tracking

bull Nuclear materials control in the case of facilities that will contain significant quantities of

nuclear materials

Nor does it focus on monitoring for non-radiological contaminants that may be of potential concern

Facility operators however should consider such contaminants when designing their monitoring

programme

113 This Safety Guide does not address monitoring for occupational exposure rather the focus is

on monitoring for disposal system performance and radiation protection of the public and the

environment Monitoring for occupational radiation protection is discussed in other IAEA safety

standards [13]

STRUCTURE

114 Section 2 provides an overview of monitoring and surveillance for radioactive waste disposal

facilities and describes overall objectives for a monitoring and surveillance programme Section 3

addresses roles and responsibilities of the regulatory body and the implementing organizations with

regard to monitoring and surveillance Sections 4 5 and 6 focus on monitoring More specifically

Section 4 addresses design of a monitoring programme and includes some consideration of strategic

issues for monitoring Section 5 provides guidance on monitoring according to the type of disposal

facility (geological near surface and facilities for mining and milling waste) Section 6 addresses

monitoring according to the stage of facility development Section 7 provides specific guidance for

surveillance activities only Finally Section 8 is concerned with the use of monitoring and surveillance

information in regard to compliance aspects and development and improvement of the safety case and

Section 9 provides a brief discussion of the salient issues pertaining to the management system for a

disposal facility

5

2 OVERVIEW OF MONITORING AND SURVEILLANCE

21 The BSS [8] defines lsquomonitoringrsquo (of public exposure) to be

ldquoThe measurement of dose or contamination for reasons related to the assessment or

control of exposure to radiation or radioactive substances and the interpretation of the

resultsrdquo

22 The IAEA Safety Guide on environmental and source monitoring [9] defines the terms lsquosource

monitoringrsquo and lsquoenvironmental monitoringrsquo as

a ldquoSource monitoring The measurement of activity in radioactive materials being

released to the environment or of external dose rates due to sources within a facility or

activityrdquo

b ldquoEnvironmental monitoring The measurement of external dose rates due to sources in

the environment or of radionuclide concentrations in environmental mediardquo

23 In the context of this Safety Guide the term monitoring refers to

Continuous or periodic observations and measurements of environmental engineering or

radiological parameters to help evaluate the behaviour of components of the waste

disposal system or of the impacts of the waste disposal system and its operation on the

public and the environment

24 Monitoring involves many characterization activities Information may have to be collected

over a period of time for a number of characterization tasks (eg groundwater flow rates moisture

content of soils daily precipitation) For other types of information once the parameter has been

defined there may be no need to continue with the sampling and measurement since it is not expected

to change in time or with development and closure of the facility (eg rock porosity)

25 Monitoring is needed to evaluate processes or parameters that are influential in the

development of the safety case The duration and frequency of monitoring may be determined by

regulatory requirements by the time scale of natural variations in a process or parameter by possible

changes associated with the construction and operation of the facility The need to address public

concern should also be considered in defining the monitoring programme

26 A programme for the surveillance of the facility should be established and implemented as

necessary and feasible It should consist of planned activities carried out to verify that the facility is

operating within the design limits and conditions and to detect any deterioration of structures systems

and components that could result in unsafe conditions [17] In the context of this Safety Guide the

term surveillance refers to

6

The physical inspection of a waste management facility in order to verify its integrity to

protect and preserve the passive safety barriers

27 Some countries do not differentiate between monitoring and surveillance of disposal facilities

28 In this respect the function of surveillance is to contribute to the detection of changes in the

engineering structures and systems of the disposal facility which might affect the radiological

performance of the system The relevant and expected changes can be identified by the post closure

safety assessment The surveillance programme is usually implemented through regular inspections of

the critical components of the waste disposal facility

29 Generally there is a need to collect site-specific data although some relevant monitoring data

may be available from other sources Safety cases are usually supported by data from a number of

sources which includes site-specific measurements regional data and generic information

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES

210 Requirement 21 of the Safety Requirements on the Disposal of Radioactive Waste [4] states

that ldquoA programme of monitoring shall be carried out prior to and during the construction and

operation of a disposal facility and after its closure if this is part of the safety case This programme

shall be designed to collect and update information necessary for the purposes of protection and safety

Information shall be obtained to confirm the conditions necessary for the safety of workers and

members of the public and protection of the environment during the period of operation of the facility

Monitoring shall also be carried out to confirm the absence of any conditions that could affect the

safety of the facility after closurerdquo

211 In addition Requirement 10 of Ref [4] indicates that ldquoAn appropriate level of surveillance and

control shall be applied to protect and preserve the passive safety features to the extent that this is

necessary so that they can fulfil the functions that they are assigned in the safety case for safety after

closurerdquo

212 Monitoring and surveillance programmes begin at site characterization phase of disposal

facility development and continue to evolve through to the post-closure period depending on the type

of the disposal facility The data collected and insights derived from monitoring should be integrated

into and inform planning decisions made throughout the life-cycle of a disposal facility As a result

provision should be made to anticipate the needs of monitoring at later periods of the facility lifetime

and to gather monitoring data that informs later planning and actions

213 Monitoring and surveillance of disposal facilities for radioactive waste has four broad

objectives

7

1 To demonstrate compliance with the regulatory constraints and licence conditions

2 To verify that the disposal system is functioning as expected This means that the components

fulfil their function as identified in the safety case and that actual conditions are consistent

with the assumptions made for post-closure safety

3 To strengthen understanding of aspects of system behaviour used in developing the safety case

for the dispoal facility and to allow further testing of models predicting those aspects

4 To accumulate an environmental database of the site the disposal facility and its surroundings

for future decisions that are part of a stepwise programme of construction operation and

closure of the disposal facility

214 As mentioned in Ref [4] ldquoMonitoring programmes are designed and implemented so as not to

reduce the overall level of safety of the facility after closurerdquo (para 54) ldquoTo some extent the safety of

a disposal facility can depend on some future actions such as maintenance work or surveillance

However this dependence has to be minimized to the extent possiblerdquo (para 322) ldquoFor a geological

disposal facility it is possible to provide for safety after closure by means of passive features In the

case of a near surface disposal facility actions such as maintenance monitoring or surveillance may

be necessary for a period of time after closure to ensure safetyrdquo (para 323)

215 The monitoring programme should be closely tied to the safety case Even if safety should not

rely on monitoring and surveillance the results of such a programme should be used to strengthen the

safety case and build confidence in safety As well information needs of the safety case should be

used to improve the monitoring program

216 Requirement 7 of Ref [4] indicates that ldquoThe host environment shall be selected the

engineered barriers of the disposal facility shall be designed and the facility shall be operated to ensure

that safety is provided by means of multiple safety functions Containment and isolation of the waste

shall be provided by means of a number of physical barriers of the disposal systemrdquo The monitoring

and surveillance programme should provide to the extent practical the necessary information to

ensure that each barrier and its associated safety function(s) performs as planned and indicated in the

safety case In addition the monitoring and surveillance programme should confirm that the

performances of the engineered and natural barriers are not damaged by the operational activities

217 Further to its technical objectives a monitoring and surveillance programme can be a suitable

tool for public reassurance In that sense consideration of public interest and interested parties

concerns may provide useful information to improve the monitoring programme by including social

aspects

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 12: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

3

Mining and Milling of Uranium and Thorium [10] Safety Reports Series No 35 on Surveillance and

Monitoring of Near Surface Disposal Facilities for Radioactive Waste [11] Safety Reports Series No

64 on Programmes and Systems for Source and Environmental Radiation Monitoring [18] and IAEA-

TECDOC-1208 on Monitoring of Geological Repositories for High Level Radioactive Waste [12]

These publications have served as resources for development of the present Safety Guide

OBJECTIVE

18 The objective of this Safety Guide is to provide guidance for monitoring and surveillance of

radioactive waste disposal facilities during their entire lifetime The Safety Guide includes the

different objectives that monitoring has at the lifetime periods from initiation of work on a candidate

site to the period after closure of the disposal facility

SCOPE

19 This Safety Guide considers the monitoring and surveillance of three types of disposal

facilities

bull Near surface disposal facilities

bull Geological disposal facilities

bull Disposal facilities for uranium and thorium mine waste

The three types of disposal facilities listed above are considered to cover all the disposal options as

identified in the Safety Requirements on Disposal of Radioactive Waste [4] In this Safety Guide

borehole disposal facilities are not specifically addressed However borehole disposal is not

conceptually different from either near surface disposal or geological disposal of radioactive waste A

possible surveillance and monitoring programme suitable for a small scale borehole disposal facility is

discussed in other IAEA Safety Standards [20]

110 As explained in Ref [14] the term near surface disposal refers generally to disposal at or

within a few tens of metres of the ground surface The term geological disposal generally refers to

disposal in deep stable geological formations usually several hundred meters or more below the

surface Mining waste disposal facilities cover a spectrum of designs from above-grade mounds to

geological disposal of tailings slimes sometimes used as backfill in old mine workings The type of

disposal is controlled by the waste characteristics and in any case the suitability of waste for disposal

in a particular disposal facility is required to be demonstrated by the safety case and supporting safety

assessment for the facility From the safety point of view disposal depth is one of the factors

considered in assessing the safety of disposal the geological environment the waste characteristics

4

and engineered features are of equal or more importance than depth of disposal in assessing the safety

of disposal facility

111 This Safety Guide places emphasis on an approach to monitoring and surveillance that

provides data needed for the development of the safety case The safety case includes information

needed for siting construct operate and close the facility for supporting decisions on managing the

disposal programme as well as information that are of particular interest to interested parties [4]

Technical details on monitoring and surveillance methodologies are beyond the scope of this Safety

Guide however Refs [10 11 12 18] direct the reader to such information and Annexes I and II give

examples of monitoring programmes for geological and near surface disposal programmes

112 This Safety Guide does not specifically address monitoring that will be required for

bull Operating personnel

bull Waste characterization or tracking

bull Nuclear materials control in the case of facilities that will contain significant quantities of

nuclear materials

Nor does it focus on monitoring for non-radiological contaminants that may be of potential concern

Facility operators however should consider such contaminants when designing their monitoring

programme

113 This Safety Guide does not address monitoring for occupational exposure rather the focus is

on monitoring for disposal system performance and radiation protection of the public and the

environment Monitoring for occupational radiation protection is discussed in other IAEA safety

standards [13]

STRUCTURE

114 Section 2 provides an overview of monitoring and surveillance for radioactive waste disposal

facilities and describes overall objectives for a monitoring and surveillance programme Section 3

addresses roles and responsibilities of the regulatory body and the implementing organizations with

regard to monitoring and surveillance Sections 4 5 and 6 focus on monitoring More specifically

Section 4 addresses design of a monitoring programme and includes some consideration of strategic

issues for monitoring Section 5 provides guidance on monitoring according to the type of disposal

facility (geological near surface and facilities for mining and milling waste) Section 6 addresses

monitoring according to the stage of facility development Section 7 provides specific guidance for

surveillance activities only Finally Section 8 is concerned with the use of monitoring and surveillance

information in regard to compliance aspects and development and improvement of the safety case and

Section 9 provides a brief discussion of the salient issues pertaining to the management system for a

disposal facility

5

2 OVERVIEW OF MONITORING AND SURVEILLANCE

21 The BSS [8] defines lsquomonitoringrsquo (of public exposure) to be

ldquoThe measurement of dose or contamination for reasons related to the assessment or

control of exposure to radiation or radioactive substances and the interpretation of the

resultsrdquo

22 The IAEA Safety Guide on environmental and source monitoring [9] defines the terms lsquosource

monitoringrsquo and lsquoenvironmental monitoringrsquo as

a ldquoSource monitoring The measurement of activity in radioactive materials being

released to the environment or of external dose rates due to sources within a facility or

activityrdquo

b ldquoEnvironmental monitoring The measurement of external dose rates due to sources in

the environment or of radionuclide concentrations in environmental mediardquo

23 In the context of this Safety Guide the term monitoring refers to

Continuous or periodic observations and measurements of environmental engineering or

radiological parameters to help evaluate the behaviour of components of the waste

disposal system or of the impacts of the waste disposal system and its operation on the

public and the environment

24 Monitoring involves many characterization activities Information may have to be collected

over a period of time for a number of characterization tasks (eg groundwater flow rates moisture

content of soils daily precipitation) For other types of information once the parameter has been

defined there may be no need to continue with the sampling and measurement since it is not expected

to change in time or with development and closure of the facility (eg rock porosity)

25 Monitoring is needed to evaluate processes or parameters that are influential in the

development of the safety case The duration and frequency of monitoring may be determined by

regulatory requirements by the time scale of natural variations in a process or parameter by possible

changes associated with the construction and operation of the facility The need to address public

concern should also be considered in defining the monitoring programme

26 A programme for the surveillance of the facility should be established and implemented as

necessary and feasible It should consist of planned activities carried out to verify that the facility is

operating within the design limits and conditions and to detect any deterioration of structures systems

and components that could result in unsafe conditions [17] In the context of this Safety Guide the

term surveillance refers to

6

The physical inspection of a waste management facility in order to verify its integrity to

protect and preserve the passive safety barriers

27 Some countries do not differentiate between monitoring and surveillance of disposal facilities

28 In this respect the function of surveillance is to contribute to the detection of changes in the

engineering structures and systems of the disposal facility which might affect the radiological

performance of the system The relevant and expected changes can be identified by the post closure

safety assessment The surveillance programme is usually implemented through regular inspections of

the critical components of the waste disposal facility

29 Generally there is a need to collect site-specific data although some relevant monitoring data

may be available from other sources Safety cases are usually supported by data from a number of

sources which includes site-specific measurements regional data and generic information

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES

210 Requirement 21 of the Safety Requirements on the Disposal of Radioactive Waste [4] states

that ldquoA programme of monitoring shall be carried out prior to and during the construction and

operation of a disposal facility and after its closure if this is part of the safety case This programme

shall be designed to collect and update information necessary for the purposes of protection and safety

Information shall be obtained to confirm the conditions necessary for the safety of workers and

members of the public and protection of the environment during the period of operation of the facility

Monitoring shall also be carried out to confirm the absence of any conditions that could affect the

safety of the facility after closurerdquo

211 In addition Requirement 10 of Ref [4] indicates that ldquoAn appropriate level of surveillance and

control shall be applied to protect and preserve the passive safety features to the extent that this is

necessary so that they can fulfil the functions that they are assigned in the safety case for safety after

closurerdquo

212 Monitoring and surveillance programmes begin at site characterization phase of disposal

facility development and continue to evolve through to the post-closure period depending on the type

of the disposal facility The data collected and insights derived from monitoring should be integrated

into and inform planning decisions made throughout the life-cycle of a disposal facility As a result

provision should be made to anticipate the needs of monitoring at later periods of the facility lifetime

and to gather monitoring data that informs later planning and actions

213 Monitoring and surveillance of disposal facilities for radioactive waste has four broad

objectives

7

1 To demonstrate compliance with the regulatory constraints and licence conditions

2 To verify that the disposal system is functioning as expected This means that the components

fulfil their function as identified in the safety case and that actual conditions are consistent

with the assumptions made for post-closure safety

3 To strengthen understanding of aspects of system behaviour used in developing the safety case

for the dispoal facility and to allow further testing of models predicting those aspects

4 To accumulate an environmental database of the site the disposal facility and its surroundings

for future decisions that are part of a stepwise programme of construction operation and

closure of the disposal facility

214 As mentioned in Ref [4] ldquoMonitoring programmes are designed and implemented so as not to

reduce the overall level of safety of the facility after closurerdquo (para 54) ldquoTo some extent the safety of

a disposal facility can depend on some future actions such as maintenance work or surveillance

However this dependence has to be minimized to the extent possiblerdquo (para 322) ldquoFor a geological

disposal facility it is possible to provide for safety after closure by means of passive features In the

case of a near surface disposal facility actions such as maintenance monitoring or surveillance may

be necessary for a period of time after closure to ensure safetyrdquo (para 323)

215 The monitoring programme should be closely tied to the safety case Even if safety should not

rely on monitoring and surveillance the results of such a programme should be used to strengthen the

safety case and build confidence in safety As well information needs of the safety case should be

used to improve the monitoring program

216 Requirement 7 of Ref [4] indicates that ldquoThe host environment shall be selected the

engineered barriers of the disposal facility shall be designed and the facility shall be operated to ensure

that safety is provided by means of multiple safety functions Containment and isolation of the waste

shall be provided by means of a number of physical barriers of the disposal systemrdquo The monitoring

and surveillance programme should provide to the extent practical the necessary information to

ensure that each barrier and its associated safety function(s) performs as planned and indicated in the

safety case In addition the monitoring and surveillance programme should confirm that the

performances of the engineered and natural barriers are not damaged by the operational activities

217 Further to its technical objectives a monitoring and surveillance programme can be a suitable

tool for public reassurance In that sense consideration of public interest and interested parties

concerns may provide useful information to improve the monitoring programme by including social

aspects

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 13: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

4

and engineered features are of equal or more importance than depth of disposal in assessing the safety

of disposal facility

111 This Safety Guide places emphasis on an approach to monitoring and surveillance that

provides data needed for the development of the safety case The safety case includes information

needed for siting construct operate and close the facility for supporting decisions on managing the

disposal programme as well as information that are of particular interest to interested parties [4]

Technical details on monitoring and surveillance methodologies are beyond the scope of this Safety

Guide however Refs [10 11 12 18] direct the reader to such information and Annexes I and II give

examples of monitoring programmes for geological and near surface disposal programmes

112 This Safety Guide does not specifically address monitoring that will be required for

bull Operating personnel

bull Waste characterization or tracking

bull Nuclear materials control in the case of facilities that will contain significant quantities of

nuclear materials

Nor does it focus on monitoring for non-radiological contaminants that may be of potential concern

Facility operators however should consider such contaminants when designing their monitoring

programme

113 This Safety Guide does not address monitoring for occupational exposure rather the focus is

on monitoring for disposal system performance and radiation protection of the public and the

environment Monitoring for occupational radiation protection is discussed in other IAEA safety

standards [13]

STRUCTURE

114 Section 2 provides an overview of monitoring and surveillance for radioactive waste disposal

facilities and describes overall objectives for a monitoring and surveillance programme Section 3

addresses roles and responsibilities of the regulatory body and the implementing organizations with

regard to monitoring and surveillance Sections 4 5 and 6 focus on monitoring More specifically

Section 4 addresses design of a monitoring programme and includes some consideration of strategic

issues for monitoring Section 5 provides guidance on monitoring according to the type of disposal

facility (geological near surface and facilities for mining and milling waste) Section 6 addresses

monitoring according to the stage of facility development Section 7 provides specific guidance for

surveillance activities only Finally Section 8 is concerned with the use of monitoring and surveillance

information in regard to compliance aspects and development and improvement of the safety case and

Section 9 provides a brief discussion of the salient issues pertaining to the management system for a

disposal facility

5

2 OVERVIEW OF MONITORING AND SURVEILLANCE

21 The BSS [8] defines lsquomonitoringrsquo (of public exposure) to be

ldquoThe measurement of dose or contamination for reasons related to the assessment or

control of exposure to radiation or radioactive substances and the interpretation of the

resultsrdquo

22 The IAEA Safety Guide on environmental and source monitoring [9] defines the terms lsquosource

monitoringrsquo and lsquoenvironmental monitoringrsquo as

a ldquoSource monitoring The measurement of activity in radioactive materials being

released to the environment or of external dose rates due to sources within a facility or

activityrdquo

b ldquoEnvironmental monitoring The measurement of external dose rates due to sources in

the environment or of radionuclide concentrations in environmental mediardquo

23 In the context of this Safety Guide the term monitoring refers to

Continuous or periodic observations and measurements of environmental engineering or

radiological parameters to help evaluate the behaviour of components of the waste

disposal system or of the impacts of the waste disposal system and its operation on the

public and the environment

24 Monitoring involves many characterization activities Information may have to be collected

over a period of time for a number of characterization tasks (eg groundwater flow rates moisture

content of soils daily precipitation) For other types of information once the parameter has been

defined there may be no need to continue with the sampling and measurement since it is not expected

to change in time or with development and closure of the facility (eg rock porosity)

25 Monitoring is needed to evaluate processes or parameters that are influential in the

development of the safety case The duration and frequency of monitoring may be determined by

regulatory requirements by the time scale of natural variations in a process or parameter by possible

changes associated with the construction and operation of the facility The need to address public

concern should also be considered in defining the monitoring programme

26 A programme for the surveillance of the facility should be established and implemented as

necessary and feasible It should consist of planned activities carried out to verify that the facility is

operating within the design limits and conditions and to detect any deterioration of structures systems

and components that could result in unsafe conditions [17] In the context of this Safety Guide the

term surveillance refers to

6

The physical inspection of a waste management facility in order to verify its integrity to

protect and preserve the passive safety barriers

27 Some countries do not differentiate between monitoring and surveillance of disposal facilities

28 In this respect the function of surveillance is to contribute to the detection of changes in the

engineering structures and systems of the disposal facility which might affect the radiological

performance of the system The relevant and expected changes can be identified by the post closure

safety assessment The surveillance programme is usually implemented through regular inspections of

the critical components of the waste disposal facility

29 Generally there is a need to collect site-specific data although some relevant monitoring data

may be available from other sources Safety cases are usually supported by data from a number of

sources which includes site-specific measurements regional data and generic information

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES

210 Requirement 21 of the Safety Requirements on the Disposal of Radioactive Waste [4] states

that ldquoA programme of monitoring shall be carried out prior to and during the construction and

operation of a disposal facility and after its closure if this is part of the safety case This programme

shall be designed to collect and update information necessary for the purposes of protection and safety

Information shall be obtained to confirm the conditions necessary for the safety of workers and

members of the public and protection of the environment during the period of operation of the facility

Monitoring shall also be carried out to confirm the absence of any conditions that could affect the

safety of the facility after closurerdquo

211 In addition Requirement 10 of Ref [4] indicates that ldquoAn appropriate level of surveillance and

control shall be applied to protect and preserve the passive safety features to the extent that this is

necessary so that they can fulfil the functions that they are assigned in the safety case for safety after

closurerdquo

212 Monitoring and surveillance programmes begin at site characterization phase of disposal

facility development and continue to evolve through to the post-closure period depending on the type

of the disposal facility The data collected and insights derived from monitoring should be integrated

into and inform planning decisions made throughout the life-cycle of a disposal facility As a result

provision should be made to anticipate the needs of monitoring at later periods of the facility lifetime

and to gather monitoring data that informs later planning and actions

213 Monitoring and surveillance of disposal facilities for radioactive waste has four broad

objectives

7

1 To demonstrate compliance with the regulatory constraints and licence conditions

2 To verify that the disposal system is functioning as expected This means that the components

fulfil their function as identified in the safety case and that actual conditions are consistent

with the assumptions made for post-closure safety

3 To strengthen understanding of aspects of system behaviour used in developing the safety case

for the dispoal facility and to allow further testing of models predicting those aspects

4 To accumulate an environmental database of the site the disposal facility and its surroundings

for future decisions that are part of a stepwise programme of construction operation and

closure of the disposal facility

214 As mentioned in Ref [4] ldquoMonitoring programmes are designed and implemented so as not to

reduce the overall level of safety of the facility after closurerdquo (para 54) ldquoTo some extent the safety of

a disposal facility can depend on some future actions such as maintenance work or surveillance

However this dependence has to be minimized to the extent possiblerdquo (para 322) ldquoFor a geological

disposal facility it is possible to provide for safety after closure by means of passive features In the

case of a near surface disposal facility actions such as maintenance monitoring or surveillance may

be necessary for a period of time after closure to ensure safetyrdquo (para 323)

215 The monitoring programme should be closely tied to the safety case Even if safety should not

rely on monitoring and surveillance the results of such a programme should be used to strengthen the

safety case and build confidence in safety As well information needs of the safety case should be

used to improve the monitoring program

216 Requirement 7 of Ref [4] indicates that ldquoThe host environment shall be selected the

engineered barriers of the disposal facility shall be designed and the facility shall be operated to ensure

that safety is provided by means of multiple safety functions Containment and isolation of the waste

shall be provided by means of a number of physical barriers of the disposal systemrdquo The monitoring

and surveillance programme should provide to the extent practical the necessary information to

ensure that each barrier and its associated safety function(s) performs as planned and indicated in the

safety case In addition the monitoring and surveillance programme should confirm that the

performances of the engineered and natural barriers are not damaged by the operational activities

217 Further to its technical objectives a monitoring and surveillance programme can be a suitable

tool for public reassurance In that sense consideration of public interest and interested parties

concerns may provide useful information to improve the monitoring programme by including social

aspects

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 14: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

5

2 OVERVIEW OF MONITORING AND SURVEILLANCE

21 The BSS [8] defines lsquomonitoringrsquo (of public exposure) to be

ldquoThe measurement of dose or contamination for reasons related to the assessment or

control of exposure to radiation or radioactive substances and the interpretation of the

resultsrdquo

22 The IAEA Safety Guide on environmental and source monitoring [9] defines the terms lsquosource

monitoringrsquo and lsquoenvironmental monitoringrsquo as

a ldquoSource monitoring The measurement of activity in radioactive materials being

released to the environment or of external dose rates due to sources within a facility or

activityrdquo

b ldquoEnvironmental monitoring The measurement of external dose rates due to sources in

the environment or of radionuclide concentrations in environmental mediardquo

23 In the context of this Safety Guide the term monitoring refers to

Continuous or periodic observations and measurements of environmental engineering or

radiological parameters to help evaluate the behaviour of components of the waste

disposal system or of the impacts of the waste disposal system and its operation on the

public and the environment

24 Monitoring involves many characterization activities Information may have to be collected

over a period of time for a number of characterization tasks (eg groundwater flow rates moisture

content of soils daily precipitation) For other types of information once the parameter has been

defined there may be no need to continue with the sampling and measurement since it is not expected

to change in time or with development and closure of the facility (eg rock porosity)

25 Monitoring is needed to evaluate processes or parameters that are influential in the

development of the safety case The duration and frequency of monitoring may be determined by

regulatory requirements by the time scale of natural variations in a process or parameter by possible

changes associated with the construction and operation of the facility The need to address public

concern should also be considered in defining the monitoring programme

26 A programme for the surveillance of the facility should be established and implemented as

necessary and feasible It should consist of planned activities carried out to verify that the facility is

operating within the design limits and conditions and to detect any deterioration of structures systems

and components that could result in unsafe conditions [17] In the context of this Safety Guide the

term surveillance refers to

6

The physical inspection of a waste management facility in order to verify its integrity to

protect and preserve the passive safety barriers

27 Some countries do not differentiate between monitoring and surveillance of disposal facilities

28 In this respect the function of surveillance is to contribute to the detection of changes in the

engineering structures and systems of the disposal facility which might affect the radiological

performance of the system The relevant and expected changes can be identified by the post closure

safety assessment The surveillance programme is usually implemented through regular inspections of

the critical components of the waste disposal facility

29 Generally there is a need to collect site-specific data although some relevant monitoring data

may be available from other sources Safety cases are usually supported by data from a number of

sources which includes site-specific measurements regional data and generic information

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES

210 Requirement 21 of the Safety Requirements on the Disposal of Radioactive Waste [4] states

that ldquoA programme of monitoring shall be carried out prior to and during the construction and

operation of a disposal facility and after its closure if this is part of the safety case This programme

shall be designed to collect and update information necessary for the purposes of protection and safety

Information shall be obtained to confirm the conditions necessary for the safety of workers and

members of the public and protection of the environment during the period of operation of the facility

Monitoring shall also be carried out to confirm the absence of any conditions that could affect the

safety of the facility after closurerdquo

211 In addition Requirement 10 of Ref [4] indicates that ldquoAn appropriate level of surveillance and

control shall be applied to protect and preserve the passive safety features to the extent that this is

necessary so that they can fulfil the functions that they are assigned in the safety case for safety after

closurerdquo

212 Monitoring and surveillance programmes begin at site characterization phase of disposal

facility development and continue to evolve through to the post-closure period depending on the type

of the disposal facility The data collected and insights derived from monitoring should be integrated

into and inform planning decisions made throughout the life-cycle of a disposal facility As a result

provision should be made to anticipate the needs of monitoring at later periods of the facility lifetime

and to gather monitoring data that informs later planning and actions

213 Monitoring and surveillance of disposal facilities for radioactive waste has four broad

objectives

7

1 To demonstrate compliance with the regulatory constraints and licence conditions

2 To verify that the disposal system is functioning as expected This means that the components

fulfil their function as identified in the safety case and that actual conditions are consistent

with the assumptions made for post-closure safety

3 To strengthen understanding of aspects of system behaviour used in developing the safety case

for the dispoal facility and to allow further testing of models predicting those aspects

4 To accumulate an environmental database of the site the disposal facility and its surroundings

for future decisions that are part of a stepwise programme of construction operation and

closure of the disposal facility

214 As mentioned in Ref [4] ldquoMonitoring programmes are designed and implemented so as not to

reduce the overall level of safety of the facility after closurerdquo (para 54) ldquoTo some extent the safety of

a disposal facility can depend on some future actions such as maintenance work or surveillance

However this dependence has to be minimized to the extent possiblerdquo (para 322) ldquoFor a geological

disposal facility it is possible to provide for safety after closure by means of passive features In the

case of a near surface disposal facility actions such as maintenance monitoring or surveillance may

be necessary for a period of time after closure to ensure safetyrdquo (para 323)

215 The monitoring programme should be closely tied to the safety case Even if safety should not

rely on monitoring and surveillance the results of such a programme should be used to strengthen the

safety case and build confidence in safety As well information needs of the safety case should be

used to improve the monitoring program

216 Requirement 7 of Ref [4] indicates that ldquoThe host environment shall be selected the

engineered barriers of the disposal facility shall be designed and the facility shall be operated to ensure

that safety is provided by means of multiple safety functions Containment and isolation of the waste

shall be provided by means of a number of physical barriers of the disposal systemrdquo The monitoring

and surveillance programme should provide to the extent practical the necessary information to

ensure that each barrier and its associated safety function(s) performs as planned and indicated in the

safety case In addition the monitoring and surveillance programme should confirm that the

performances of the engineered and natural barriers are not damaged by the operational activities

217 Further to its technical objectives a monitoring and surveillance programme can be a suitable

tool for public reassurance In that sense consideration of public interest and interested parties

concerns may provide useful information to improve the monitoring programme by including social

aspects

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 15: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

6

The physical inspection of a waste management facility in order to verify its integrity to

protect and preserve the passive safety barriers

27 Some countries do not differentiate between monitoring and surveillance of disposal facilities

28 In this respect the function of surveillance is to contribute to the detection of changes in the

engineering structures and systems of the disposal facility which might affect the radiological

performance of the system The relevant and expected changes can be identified by the post closure

safety assessment The surveillance programme is usually implemented through regular inspections of

the critical components of the waste disposal facility

29 Generally there is a need to collect site-specific data although some relevant monitoring data

may be available from other sources Safety cases are usually supported by data from a number of

sources which includes site-specific measurements regional data and generic information

GENERAL OBJECTIVES FOR MONITORING AND SURVEILLANCE OF DISPOSAL

FACILITIES

210 Requirement 21 of the Safety Requirements on the Disposal of Radioactive Waste [4] states

that ldquoA programme of monitoring shall be carried out prior to and during the construction and

operation of a disposal facility and after its closure if this is part of the safety case This programme

shall be designed to collect and update information necessary for the purposes of protection and safety

Information shall be obtained to confirm the conditions necessary for the safety of workers and

members of the public and protection of the environment during the period of operation of the facility

Monitoring shall also be carried out to confirm the absence of any conditions that could affect the

safety of the facility after closurerdquo

211 In addition Requirement 10 of Ref [4] indicates that ldquoAn appropriate level of surveillance and

control shall be applied to protect and preserve the passive safety features to the extent that this is

necessary so that they can fulfil the functions that they are assigned in the safety case for safety after

closurerdquo

212 Monitoring and surveillance programmes begin at site characterization phase of disposal

facility development and continue to evolve through to the post-closure period depending on the type

of the disposal facility The data collected and insights derived from monitoring should be integrated

into and inform planning decisions made throughout the life-cycle of a disposal facility As a result

provision should be made to anticipate the needs of monitoring at later periods of the facility lifetime

and to gather monitoring data that informs later planning and actions

213 Monitoring and surveillance of disposal facilities for radioactive waste has four broad

objectives

7

1 To demonstrate compliance with the regulatory constraints and licence conditions

2 To verify that the disposal system is functioning as expected This means that the components

fulfil their function as identified in the safety case and that actual conditions are consistent

with the assumptions made for post-closure safety

3 To strengthen understanding of aspects of system behaviour used in developing the safety case

for the dispoal facility and to allow further testing of models predicting those aspects

4 To accumulate an environmental database of the site the disposal facility and its surroundings

for future decisions that are part of a stepwise programme of construction operation and

closure of the disposal facility

214 As mentioned in Ref [4] ldquoMonitoring programmes are designed and implemented so as not to

reduce the overall level of safety of the facility after closurerdquo (para 54) ldquoTo some extent the safety of

a disposal facility can depend on some future actions such as maintenance work or surveillance

However this dependence has to be minimized to the extent possiblerdquo (para 322) ldquoFor a geological

disposal facility it is possible to provide for safety after closure by means of passive features In the

case of a near surface disposal facility actions such as maintenance monitoring or surveillance may

be necessary for a period of time after closure to ensure safetyrdquo (para 323)

215 The monitoring programme should be closely tied to the safety case Even if safety should not

rely on monitoring and surveillance the results of such a programme should be used to strengthen the

safety case and build confidence in safety As well information needs of the safety case should be

used to improve the monitoring program

216 Requirement 7 of Ref [4] indicates that ldquoThe host environment shall be selected the

engineered barriers of the disposal facility shall be designed and the facility shall be operated to ensure

that safety is provided by means of multiple safety functions Containment and isolation of the waste

shall be provided by means of a number of physical barriers of the disposal systemrdquo The monitoring

and surveillance programme should provide to the extent practical the necessary information to

ensure that each barrier and its associated safety function(s) performs as planned and indicated in the

safety case In addition the monitoring and surveillance programme should confirm that the

performances of the engineered and natural barriers are not damaged by the operational activities

217 Further to its technical objectives a monitoring and surveillance programme can be a suitable

tool for public reassurance In that sense consideration of public interest and interested parties

concerns may provide useful information to improve the monitoring programme by including social

aspects

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 16: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

7

1 To demonstrate compliance with the regulatory constraints and licence conditions

2 To verify that the disposal system is functioning as expected This means that the components

fulfil their function as identified in the safety case and that actual conditions are consistent

with the assumptions made for post-closure safety

3 To strengthen understanding of aspects of system behaviour used in developing the safety case

for the dispoal facility and to allow further testing of models predicting those aspects

4 To accumulate an environmental database of the site the disposal facility and its surroundings

for future decisions that are part of a stepwise programme of construction operation and

closure of the disposal facility

214 As mentioned in Ref [4] ldquoMonitoring programmes are designed and implemented so as not to

reduce the overall level of safety of the facility after closurerdquo (para 54) ldquoTo some extent the safety of

a disposal facility can depend on some future actions such as maintenance work or surveillance

However this dependence has to be minimized to the extent possiblerdquo (para 322) ldquoFor a geological

disposal facility it is possible to provide for safety after closure by means of passive features In the

case of a near surface disposal facility actions such as maintenance monitoring or surveillance may

be necessary for a period of time after closure to ensure safetyrdquo (para 323)

215 The monitoring programme should be closely tied to the safety case Even if safety should not

rely on monitoring and surveillance the results of such a programme should be used to strengthen the

safety case and build confidence in safety As well information needs of the safety case should be

used to improve the monitoring program

216 Requirement 7 of Ref [4] indicates that ldquoThe host environment shall be selected the

engineered barriers of the disposal facility shall be designed and the facility shall be operated to ensure

that safety is provided by means of multiple safety functions Containment and isolation of the waste

shall be provided by means of a number of physical barriers of the disposal systemrdquo The monitoring

and surveillance programme should provide to the extent practical the necessary information to

ensure that each barrier and its associated safety function(s) performs as planned and indicated in the

safety case In addition the monitoring and surveillance programme should confirm that the

performances of the engineered and natural barriers are not damaged by the operational activities

217 Further to its technical objectives a monitoring and surveillance programme can be a suitable

tool for public reassurance In that sense consideration of public interest and interested parties

concerns may provide useful information to improve the monitoring programme by including social

aspects

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 17: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

9

3 RESPONSIBILITIES OF THE OPERATOR AND REGULATORY BODY

REGARDING MONITORING AND SURVEILLANCE PROGRAMMES

RESPONSIBILITIES OF THE OPERATOR

31 The operator of the waste disposal facility should be responsible for implementing the items

provided in para 32 If a change in responsibilities occurs after closure of the facility the new

responsible organization should also take measures to ensure that the monitoring and

surveillance programmes continue in the post-closure phase in a manner that meets national

regulatory requirements and policies

32 With regard to responsibilities related to monitoring and surveillance the operator should

a) Design the monitoring and surveillance programme that meets the requirements established by

national regulatory bodies If the programme is a part of the safety case it should be designed

throughout the pre-operational operational and post-closure periods of the facility

b) Perform adequate monitoring and surveillance along with the programmes reviewed by

national regulatory bodies as follows

i For the construction stage in pre-operational period This stage includes baseline

monitoring

ii During and after operations that will permit unexpected system behaviour to be

detected

c) Develop contingency plans to address unexpected system behaviour and emergency plans to

address unacceptable system behaviour

d) Report the status of the monitoring and surveillance to the regulatory body periodically and

report unexpected or emergency circumstances where they occur

RESPONSIBILITIES OF THE REGULATORY BODY

33 The regulatory body should provide the necessary requirements on the programme and

implementation of the monitoring and surveillance for the disposal facility and should be responsible

for implementing the items provided in para 34 The guidance necessary for the disposal facility

operator or responsible organization should be provided to establish a monitoring and surveillance

programmes for all periods of the disposal process including indications on the duration of monitoring

and surveillance in the post-closure period

34 With regard to specific responsibilities related to monitoring and surveillance the regulatory

body should

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 18: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

10

(a) Periodically review the regulation in force for monitoring and surveillance the monitoring and

surveillance programmes and reporting arrangements including arrangements for emergency

monitoring

(b) Review the monitoring and surveillance data provided by operators against established

requirements

(c) Provide evidence that waste disposal facility is being appropriately monitored and controlled

by operators this may include independent monitoring and surveillance

35 Specific responsibilities relevant to source and environmental monitoring as well as

surveillance may be delegated by a government or regulatory body to other agencies In deciding on

the delegation of specific responsibilities to other organizations the regulatory body should pay due

attention to the availability in these organizations of suitably qualified and experienced personnel

appropriate analytical techniques and equipment and an appropriate management system The

regulatory body as well as other organizations to which responsibilities have been delegated should

be independent of those organizations that are responsible for the promotion and development of the

waste disposal facility

36 Examples of the delegation of authority may concern

(a) The design and regular performance of the confirmatory programmes of source and

environmental monitoring This may be a programme carried out to assess the cumulative

radiological impact of multiple or related facilities when they have an impact on the same

areas and the same population groups

(b) The confirmatory assessment of the doses to members of the public to warrant that they are

maintained below the limits established in licences

(c) Security and emergency response

37 Other agencies may also be responsible for other domains relating to monitoring such as

(a) Collection and retention of data provided by operators governmental or international

agencies

(b) Environmental monitoring at the national level

(c) Establishing standards

38 The regulatory body should liaise with these agencies as appropriate

If the potential exists for an accident the regulatory body should ensure that emergency preparedness

arrangements are in place and are routinely tested The arrangements should include provision for

rapid large scale monitoring if conditions suggest such a possibility This may be performed by a

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 19: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

11

designated responsible organization with the requisite capability or by the regulatory body itself The

required monitoring may include both source environmental and individual monitoring

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 20: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

13

4 DESIGN OF A MONITORING PROGRAMME

41 The monitoring programme for a disposal facility should be defined to respond to the

objectives stated in Section 2 It should include source and environmental monitoring programmes to

assess public exposure and impact on the environment as well as to assess potential release pathways

Generic aspects of source and environmental monitoring for waste disposal facilities are dealt with in

Ref [9] The monitoring programme should also assess the functioning of the disposal system with

respect to operational and long term safety

42 While initial monitoring plans should address all periods of the disposal project they should

also remain flexible given the time scale of siting construction operation and closure of a facility

This should allow integrating lessons learnt from prior periods to adapt to new technology and to

respond to potential future regulatory requirements design changes etc while at the same time

maintaining data continuity and comparability It should also allow implementing additional

monitoring if concerns arise with regard to disposal facility performance Guidance specific to the

three main periods of facility development is provided in Section 6

43 The monitoring programme should be designed using a graded approach so that the most

significant efforts are placed in areas where the consequence of a malfunction or failure of a

component could have an impact on safety or in areas where an abnormal or unexpected behaviour of

the disposal facility can be detected as soon as possible

44 Designing and carrying out a monitoring programme must take into considerations the

technical constraints imposed by the context and environment in which monitoring is carried out In

practice monitoring will rely on on-site or remote instrumentation (eg sensors) visual inspections

sampling and analysis of samples as well as analysis and interpretation of data to ensure that

information gained from monitoring is representative of disposal system behaviour or of potential

impact on public health and environment

45 Indirect measurements of a parameter of interest are another useful approach where direct in-

situ measurements cannot be carried out For example it may be easier to monitor a temperature

gradient than relative saturation of a swelling clay buffer or host rock Thermal conductivity and

ultimately relative saturation can be deduced from a thermal gradient measurement

46 Monitoring specific evolutions behind engineered barriers should not degrade barrier function

It will be necessary to demonstrate either that any remaining physical links (such as wiring) respect

this constraint or that such links can be removed leaving an undisturbed barrier once monitoring is

done Non-intrusive monitoring may provide one alternative approach The use of wireless signal

transmission may provide another alternative approach In addition monitoring at alternative facility

with similar characteristics or pilot facility may also be useful

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 21: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

14

47 A monitoring programme should ensure that data is analysed promptly to provide the

operators and decision makers with timely information on disposal facility management In particular

the regulator should receive a summary of monitoring results and interpretation at defined intervals

and should be informed promptly of any unexpected results that could have an impact on safety (for

example data on significant increase in environmental radiation levels data suggesting the disposal

system may not perform as anticipated)

48 The design of the post-closure monitoring programme should be closely linked to and guided

by the findings of the safety case and supporting safety assessments so that in particular in the case of

near surface disposal facilities the results of the monitoring can be applied to confirm the assumptions

made for the period after closure

49 The design of the monitoring programme should be the result of an optimization process in

which costs and benefits from monitoring are taken into consideration The coverage intensity and

duration of monitoring also translates into a cost both direct (related to monitoring equipment and

activity and ensuing worker risk) and indirect (related to maintaining and operating the facility in a

state allowing such activity)

410 The monitoring programme considering all periods of the facility lifetime should be early

reviewed and approved by the regulatory body The monitoring programme should begin as early as

possible during the initial site selection process and should evolve through the construction operation

and closure of the facility in an ongoing manner informing and updating data used in the safety case

and supporting safety assessments of the facility as illustrated in Fig 1 In parallel the monitoring

programme should be periodically reviewed by the regulatory body

411 In designing the monitoring programme it should be considered that the credibility of

monitoring data need to be verified using sufficient redundancy independent verification of values

use of robust equipment and design and to the extent possible use of analogue situations

412 The general objective of monitoring programmes during the pre-operational period is to

establish natural background levels of contaminants and to establish natural characteristics of features

events and processes (FEPs) occurring in the environment of the disposal facility which may

influence the design and subsequent short and long term performance of the facility (eg water table

fluctuations) In this regard the monitoring programme should be closely integrated with the safety

case and safety assessment and with construction and operation procedures A database should be

developed that allows identification of trends and from which insights can be obtained This database

should allow discrimination of the effects of the presence of the facility as it evolves in time which

can then be used to update the safety case

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 22: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

15

FIG 1 Role of monitoring in the lifetime of a disposal facility for radioactive waste

Baseline monitoring ndash for collection of data to support siting process and identification of important FEPs for first iteration of the safety case

Monitoring of ldquoas builtrdquo facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps Additional measurements to be introduced at this step

Monitoring of operational facility minus for compliance evaluation and to support development of safety case for subsequent licensing steps

Monitoring of the post closure performance of the disposal facility (if applicable) minus for compliance evaluation and to support subsequent decisions (eg scale back monitoring release from regulatory control)

Monitoring for closure minus for compliance evaluation to support closure activities and subsequent post-closure monitoring Additional measurements may be introduced at this step while others will be discontinued

Site Selection

Facility Construction

Facility Operation

Facility Closure

Post-closure period

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 23: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

16

413 The decision to implement monitoring after closure of the facility and its duration should be

based on the type of disposal facility and its potential hazard posed over time The duration of post

closure monitoring if any should also depend on confidence in facility performance acquired from

monitoring during previous periods The duration of post-closure monitoring should also depend on

reasonable assumptions on the duration of institutional stability and continuity of knowledge and its

consequent ability to ensure ongoing monitoring and maintenance

414 After closure monitoring may be pursued to assess overall facility function and to

periodically assess the potential impacts on the public and environment However it should be

recognized that properly designed disposal facilities (especially geological disposal facilities) are not

expected to have significant releases to the biosphere during any reasonable period of monitoring

415 The design of the monitoring programmes should consider how the results are to be

communicated to the public ensuring transparency Transparency carried with it the responsibility to

provide clear interpretation of results and the context for the measurements

416 The monitoring data can also serve to indicate when investigation of an actual or potential

inadequacy in the safety of the disposal facility is warranted If monitoring indicates unanticipated

changes that affect the safety then the safety case and the monitoring programme may need to be

revised and appropriate corrective actions may need to be taken

417 Waste disposal systems are designed on the basis of principles of passive safety and as a

general rule sudden failures are unlikely to occur conditions are rare that would necessitate

immediate or precipitate action However certain circumstances may arise that justify rapid response

For example the stability of a mine tailings dam may be threatened by an extreme rain storm event

As appropriate the possibility of a sudden failure should be taken into account in the design of a

monitoring programme

418 Key technical factors that influence the design of a monitoring programme are

bull Waste characteristics

bull Facility type and design

bull Site characteristics

bull The stage of development of the facility

419 The waste characteristics quantity of waste and time-frame of radionuclide release that is to

be expected from the disposal facility will influence the design of a monitoring program Specific

performance requirements for waste characteristics in relation to operational safety or safety after

closure may give rise to specific monitoring objectives

420 The type and design of the disposal facility influence the type amount and time-frame of

radionuclide release pathways that are to be expected from the disposal facility Specific performance

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 24: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

17

requirements for engineered barriers in relation to operational safety or safety after closure may give

rise to specific monitoring objectives The monitoring programme should also be designed to evaluate

whether any changes in the environment associated with construction of the disposal facility have

reduced favourable properties of the environment

421 The site characteristics influence the radionuclide transfer pathways from the disposal facility

to the accessible environment The primary function of monitoring the transfer pathways should be for

performance confirmation The assumptions and conclusions of the safety assessment are a key input

to identify technical monitoring objectives in relation to performance confirmation However

knowledge of transfer pathways may also help specifying a monitoring programme tailored to detect

radionuclide migration into the accessible environment

422 The periods of the disposal facility development influences the monitoring programme both in

relation to monitoring objectives that are relevant and in relation to technical constraints of

monitoring as described in Section 6

423 In general the design of the monitoring programme includes the following

bull Identification and justification of the properties processes phenomena and observable

quantities that are significant to the safety case

bull Establishing the scope and objectives for the monitoring program

bull Identification and justification of the measurement locations

bull Identification and justification of the duration and frequency of monitoring including criteria

for when monitoring may be scaled back or terminate

bull Identification and justification of the methods to be used based on the above and based on

available monitoring technology and its characteristics

bull Assessment of the robustness of the monitoring technology over the relevant time period of

the measurements

bull Establishing how the results will be used (for each type of monitoring) and communicated

bull Establishing levels for actions based on existing regulations and safety case assumptions and

models

bull Establishing decisions on what actions should be pursued in case levels for actions are

exceeded

bull Specifications of management and reporting of results of monitoring

bull Balancing the benefits of monitoring against its costs

bull Establishing a procedure for decommissioning of monitoring instrumentation

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 25: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

19

5 MONITORING BY TYPE OF DISPOSAL FACILITY

51 The objectives of the monitoring programme and most of the elements given in this Safety

Guide are common for the three types of facilities (near surface geological and disposal facilities for

mining residues) However there are some differences that need to be addressed in the strategy for

disposal which in turn lead to differences in the practical implementation of the monitoring

programme

Near Surface Disposal

52 In general wastes suitable for disposal in near surface repositories are low level waste [14]

This disposal option is suitable for waste that contains such an amount of radioactive material that

robust containment and isolation for limited periods of time typically up to a few hundred years are

required The management strategy in this case is to contain the wastes until decay has removed

sufficient radioactive material that the risk from migration of the residual radionuclides as the facility

eventually degrades is considered as acceptable In this regard the disposal philosophy is similar to

that of geological disposal for long-lived wastes but the time scales involved may be shorter

Monitoring activity associated with near surface disposal facilities containing these types of waste will

thus focus on the construction operation and closure of the facility providing confidence in the

function of the system for hundreds of years as well as monitoring radionuclides in groundwater or in

the surrounding environment

Geological Disposal

53 When compared to near surface disposal geological disposal is suitable for intermediate and

high level wastes that need a greater degree of containment and isolation from the accessible

environment in order to ensure long term safety For example radioactive wastes containing long-

lived radionuclides or wastes with specific activities high enough to generate significant quantities of

heat from radioactive decay such as spent nuclear fuel are generally disposed of within deep

geological disposal facilities with engineered barriers such that that contaminant migration into the

surrounding geosphere will not begin to occur until a period of thousands of years has elapsed The

safety strategy being employed is to contain for a sufficient period to ensure that any release to the

biosphere occurs in a slow and controlled manner In this case monitoring is focused on the

construction operation and closure of the disposal facility to provide confidence in the containment

systems Monitoring after closure of the facility if any may focus on the presence of radionuclides in

the environment As early releases to the environment are highly unlikely this kind of monitoring is

rather for the purpose of social reassurance than for ensuring the performance of the disposal system

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 26: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

20

Mining Residue Disposal

54 Mining residues can vary greatly with respect to their radiological hazards The specific

activity of the residues will be dependent upon the grade of ore mined and milled The type of ore and

its grade will thus determine the nature of the disposal system If uranium is mined and milled the

residues will remain almost as radioactive as the parent ore for periods of hundreds of thousands of

years If thorium is mined and milled the mining residues absent the parent Th 232 will decay to

insignificant levels within 50 years The disposal systems are not designed to provide absolute

containment at all times and the strategy is to control any release of radionuclides to the environment

such that an unacceptable dose does not occur Risks associated with this type of facility may be

dominated by chemical and physical risks such as long term release of potentially toxic elements and

structural failure As a result monitoring will consider the construction operation and closure of the

facility but will have greater emphasis on the presence in the surrounding environment of

radionuclides and associated chemicals that indicate how well the system is functioning

55 The programme of monitoring of a disposal facility for naturally occurring radioactive

material would be similar to that of a disposal facility for uranium or thorium mine waste The design

of such a programme should reflect a graded approach to safety

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 27: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

21

6 MONITORING IN THE DIFFERENT PERIODS OF FACILITY LIFETIME

61 Through all periods of the facility lifetime technological realities limit the robustness and

scope of what is achievable in monitoring In many cases direct measurements of key parameters or

phenomena cannot be made Instead inferential method must be used For instance regional

groundwater flow velocities are deduced from head measurements and pump tests and point

measurements These problems worsen as measurements are required from greater depths below

surface in high radiation fields or in other situations that make access more difficult Consequently

expectations about what can be achieved through monitoring should be moderated by technological

reality Monitoring expectations are necessarily limited by certain physical challenges and limitations

characteristic of different types of facilities

62 As described in Ref [12] phenomena to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

An example of monitoring parameters by categories and periods of a geological disposal facility is

provided in Annex I that lists the corresponding monitoring parameters for such a programme and at

which of the lifetime phase these parameters would be measured The technical complexity of a

monitoring programme will vary according to type of disposal facility and in turn potential risk For a

near surface disposal facility the list of parameters to be monitored would typically be less complex

than the example provided in Annex I An Example of a near surface monitoring programme is given

in Annex II

Pre-operational Period

63 Prior to operation the monitoring programme should first (prior to construction) be focussed

on site characterization This information should be used to determine site baseline conditions and site

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 28: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

22

suitability At the start of construction (but prior to operations) monitoring is used to assess the

potential impact of construction activities on the public and environment and to establish the disposal

facility ldquoas builtrdquo conditions to ensure regulatory and safety compliance [15] The objectives of the

monitoring programme during the pre-operational period are to

bull Contribute to evaluate site suitability

bull Provide input data for the design of the facility

bull Provide input data needed for the operational and post-closure safety cases

bull Define baseline conditions for comparison with later monitoring results

bull Aid in designing the operational monitoring programme

64 The safety case and supporting safety assessment provide an iterative framework for

progressively improving understanding technical aspects of the disposal system and for identifying

which new monitoring data should be collected As the safety case and safety assessment progress

through successive iterations and as key issues are identified or resolved the monitoring system

should be adapted to accommodate the needs of safety assessment evaluations Conversely as

monitoring data identifies new information it may require updating scenarios conceptual models or

parameters used as part of the demonstration of safety The progressive adaptation of the safety

assessment analysis and the associated monitoring both directed at reducing uncertainty is a key

feature of the safety assessment methodological approach

65 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility For example it will be used to evaluate changes that occur in the rock and

groundwater system during the construction and operational periods and in the post-closure stage to

evaluate any impacts that the presence of the disposal facility may have on natural processes and the

environment In practice the monitoring programme will begin during the site investigation stage A

more comprehensive description of establishing baseline conditions can be found in Ref [15]

66 Special attention should be drawn to defining a baseline for mine residue disposal facilities

Such facilities are developed for the disposal of radionuclides naturally occurring in the surroundings

As a result performance measurements taken later in the facility lifetime must be conducted in

reference to the baseline to determine changes in concentrations in environmental media By contrast

waste disposal facilities developed for the disposal of either low and intermediate level wastes or high

level waste and spent nuclear fuel characteristic radionuclides that could be observed by a monitoring

system are more easily distinguished from background For example Ref [11] notes that likely

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 29: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

23

examples for detection at near surface disposal facilities are H-3 Cs-137 and C-14 These

radionuclides are relatively easy to detect and incremental increases are more easily distinguishable

from their low levels in background than are naturally occurring radionuclides of the uranium and

thorium decay series in mining districts making the initial definition of a baseline less crucial though

still important

Operational Period

67 During the operational period the monitoring programme should contribute to operational

safety measure potential impacts on the public and environment and assess the functioning of the

disposal system Monitoring should continue to encompass evaluation of FEPs important to the safety

case as part of a confirmatory programme This provides for strengthening of the understanding of the

disposal system behaviour to refine the operational and post-closure safety cases The monitoring

programme should also be focused on collection of data from the short term performance of the lsquoas

builtrsquo disposal system to assist in confirming long term system performance The objectives of the

monitoring programme during the operational period are to provide

bull Data for confirmation of the performance of elements of the disposal system which may be

used to revise improve or build confidence in the post-closure safety case

bull Data that support the operational safety case including routine operational releases and

worker protection

68 Performance confirmation monitoring should be conducted on key technical issues of interest

for either operational or long-term performance of the disposal system It should be viewed as an

extension of the progressive improvement to the safety case which continues after the issuance of the

operational license to provide progressively better assurance of either operational or long-term safety

during the operational period The monitoring should provide additional support to the data used for

the safety assessment so that the safety assessment is updated and improved through the operational

period Regulatory authorities may require a strong programme of performance confirmation as part of

license conditions for an operational license In this way the operator may be obliged to resolve

technical issues during the period of operation rather than as a precursor to receiving an operating

license This approach can be used to manage residual uncertainties about technical issues at the time

the construction license is granted but cannot be a substitute for an appropriate level of early

regulatory scrutiny and careful consideration of uncertainties in the safety case

69 The monitoring programme needs to take account of the potential for releases associated with

facility operations as part of the operational safety case This element of the programme is intended to

protect the public and the environment during the operational stage and may be established to meet

regulatory requirements for routine and accidental releases from nuclear facilities The emergency

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 30: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

24

response programme developed as part of the operational safety case should include an appropriate

monitoring strategy that takes account of the suddenness with which emergencies can arise

Monitoring strategies of this kind will be driven by the risk associated with potential accident

scenarios envisaged and monitoring of such events will not generally be part of a routine monitoring

programme and should be considered separately

610 The monitoring programme associated with the operational safety case needs to ensure the

safety of workers at the disposal facility To accomplish this goal the monitoring programme should

be integrated with the operational safety case This includes updating the operational safety case to

ensure that safe operations can continue during the long time period in which the facility is

operational

611 Additional regulatory requirements may exist in addition to radiological monitoring and

performance confirmation requirements depending on national regulations For instance requirements

may exist to monitor groundwater for the presence of toxic chemicals and these requirements may be

entirely different than similar requirements to monitor for releases of radionuclides

Post-Closure Period

612 One objective of the monitoring programme in the period after closure if this is part of the

safety case is to measure for the presence of contaminants or radiation in the environment that could

be attributable to the disposal facility However this element of the monitoring programme is only one

part of the monitoring programme after closure and has different importance for the different types of

disposal facilities The intensity duration and importance of post-closure monitoring differ among the

types of disposal facilities

613 Monitoring in the post-closure period may be used as a tool contributing to take the decision

to move from a period of active institutional control to a period of passive institutional control At this

stage of the disposal facility system development the goal is to identify when conditions at the site

would be suitable for a license revision to allow termination of monitoring maintenance and active

control of the site To achieve this goal the monitoring programme should be focused to support the

decision processes

MONITORING FOR EMERGENCY RESPONSE

614 Monitoring for emergency response differs from routine monitoring activities in several key

regards Whereas routine monitoring is used to collect information for regulatory compliance and

updating the safety case monitoring for emergency response will have as its focus provision of

information to mitigate imminent threats to human health and the environment The ability to monitor

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 31: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

25

facility and environmental data is a requirement of a comprehensive emergency response plan and

arrangements as called for in Ref [16]

615 For some kinds of existing disposal facilities (eg past practices as some tailings dams)

emergencies can arise rapidly For instance extreme weather or seismic events can result in dam

failure with associated rapid releases of large amounts of contaminants into the environment The

safety case cannot be updated in a retrospective manner to make decisions because of the rapidity of

the event Instead emergency arrangements should be developed for the full range of postulated

events to include events with a very low estimated probability of occurrence which incorporate

monitoring personnel procedures and equipment and other arrangements that would allow rapid

identification of the emergency and imminent threats to human health and the environment as

described in Ref [9] and called for in Ref [16] The monitoring arrangements should be able to

provide data in a timely way so that appropriate responses can be taken to include default operation

intervention levels (OILs) that have been coordinated with local officials [9 16]

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 32: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

27

7 DEVELOPMENT AND IMPLEMENTATION OF A SURVEILLANCE PROGRAMME

71 The purpose of the surveillance programme is to provide for the oversight of a waste disposal

facility to verify its integrity to protect and preserve the passive safety barriers and the prompt

identification of conditions that may lead to a migration or release of radioactive and other

contaminants to the environment The surveillance programme is usually implemented through regular

inspections of the critical components of the waste disposal facility The surveillance programme

includes but is not limited to inspections Visual inspections are an important and effective way of

detecting anomalies indicative of potential failures The surveillance programme also includes review

and assessment of records trends and performance of different parameters

72 A site-specific surveillance plan and implementation procedures should be developed early in

the facility lifetime and should be periodically updated in consultation with the regulatory authority

taking into account changes in conditions at the site in operations and in technology

73 This plan should show how the surveillance results complement the monitoring programme

and site safety and performance requirements The plan should include

(a) Description of the site and adjacent area

(b) Description of components of the waste management system and environmental setting

(c) Type and frequency of inspections

(d) Inspection procedures

(e) Contingency or maintenance actions

(f) Reporting requirements for inspections

(g) Management system

SURVEILLANCE THROUGHOUT THE LIFETIME OF A DISPOSAL FACILITY

74 The monitoring and testing programme should start in the pre-operational period during

construction to allow detection of early degradation of the components integrity or to find out the

quality of the host rock around the excavations The surveillance programme to be followed when

operation of the disposal begin should be defined towards the end of the pre-operational phase [11]

75 During the operation of the facility the surveillance programme should allow the verification

that passive safety barriers integrity is protected and preserved The protective components of the

disposal facility could be inspected periodically as part of the surveillance programme as long as this

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 33: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

28

can be performed on accessible areas and may typically be restricted to disposal infrastructure and

those parts of engineered barriers directly accessible from infrastructure

76 During the period after closure waste disposal areas or cells containing waste and the

emplaced waste forms are usually not accessible for inspection Duration of the post closure

surveillance should be based on the type of disposal facility The duration of post closure surveillance

should also depend on confidence in facility performance acquired during previous periods The

duration of surveillance after closure should also depend on reasonable assumptions on the duration of

institutional stability and continuity of knowledge

SURVEILLANCE BY TYPE OF DISPOSAL FACILITY

77 For near surface disposal facilities surveillance should start in the pre-operational period and

should continue in the period after closure until the end of the active institutional control period

Barriers that could typically be inspected in the period after closure are covers of the disposal

78 For geological disposal facilities surveillance should start in the pre-operational period and

will typically ends at closure of the facility when access to the engineered barriers is no longer

possible

79 For mining residue disposal facilities surveillance should start in the pre-operational stage and

ends either at the end of the active institutional control period or at closure of the facility depending

on the nature of the disposal system - should the access to the engineered barriers be no longer

possible The assumptions on the duration of institutional stability and continuity of knowledge

usually are a major factor defining the duration of surveillance after closure An example of a long

term surveillance plan (period after closure) for a uranium mill tailings site is given in annex I of Ref

[10]

TYPE AND FREQUENCY OF INSPECTIONS

710 The programme of inspections should be based on the site-specific conditions and the

potential risk to humans and on other socioeconomic environmental and regulatory impacts associated

with the failure of the waste disposal facility A surveillance programme will usually include routine

detailed and special-purpose inspections

Visual and physical inspections may be applied to critical components of the waste management

systems thus providing an effective way of detecting anomalies indicative of potential failures Such

inspections should follow a plan including routine detailed and special purpose inspections

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 34: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

29

Routine inspections

711 This type of inspection should be undertaken on a periodic basis to ensure that the general

condition of all the components of the waste management system is satisfactory A member of the

operatorrsquos technical staff with suitable knowledge and experience of the facility will normally perform

the inspections

Detailed inspections

712 The purpose of a detailed inspection is to ensure that the waste disposal system is performing

in accordance with the design criteria and complying with regulatory requirements The inspection

should be expected to be preceded by a review of the previous inspection report looking particularly

for any items needing follow-up from the previous inspection and a review of any surveillance data

produced since the previous inspection report

713 Detailed inspections should also be performed at regular intervals throughout the construction

of a waste disposal facility and during any periods of major modification as well as during any

remediation work This is to ensure that the construction or modification is performed according to

approved plans and have not compromised the components of the disposal facility The frequency of

detailed inspections will be determined on a site specific basis

714 Detailed inspections should normally be performed by a suitably qualified individual

possessing a thorough knowledge of the disposal facility and the operational requirements

Special inspections

715 Special inspections should be conducted after natural events considered being extreme for the

disposal facility environment such as significant fires major earthquakes floods severe storms very

heavy rainfall or cyclones Special inspections should also be performed in case of events like

incidents The purpose of these special inspections is to ensure that the components of the waste

management system have not been damaged by these events and continue to be fully functional

716 Such inspections are carried out by suitably trained personnel who can determine whether

specialised technical assistance is necessary

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 35: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

31

8 USE OF MONITORING AND SURVEILLANCE INFORMATION

81 As discussed in previous sections monitoring and surveillance information is collected for the

purpose of reduction of risk or uncertainty with a view to updating the safety case The use of

monitoring and surveillance information should therefore be in line with these purposes Users of

monitoring and surveillance information should be all interested parties including the operator the

regulatory body and other concerned interested parties By including all interested parties in the use of

monitoring and surveillance information the goal is to achieve improved transparency of the disposal

process the evolution of the disposal facility protection of the public and environment and barrier

performance

82 Monitoring information will always have some degree of uncertainty Managing the residual

uncertainties in measurement and understanding of the disposal facility is a primary function of the

safety case development Issues with the use of monitoring information include difficulties in

resolving spatial and temporal variability inability to directly measure parameters of interest inability

to project future system behaviour and lack of fundamental understanding of some processes of

interest For example over the lifetime of many disposal facilities there may be significant changes in

climatic patterns and associated shifts in human behaviour and practices The ability to project system

behaviour into the distant future will always be uncertain These changes could affect the potential

release of radionuclides from disposal facilities and the exposure pathways through which biota and

representative person exposure to radionuclides may occur

83 Caution should be used in applying available monitoring information The credibility of

monitoring data should be verified using sufficient redundancy (which should be part of the

monitoring system design) independent verification of values use of robust equipment and design

and to the extent possible use of analogue situations

ANALYSIS OF AND RESPONSE TO MAIN OBJECTIVES

84 Monitoring and surveillance in all periods should provide data on the disposal system for

regulatory compliance orand provide data that are used in the development and incremental

improvement of the safety case These two purposes will in some cases overlap for example a license

condition requiring a deeper understanding of FEPs will lead to improvement of the safety case

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 36: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

32

Use of Monitoring and Surveillance Information for Regulatory Compliance

85 At the minimum monitoring and surveillance results should contribute to demonstrate

compliance with the regulatory constraints and licence conditions The operator of a disposal facility

may base some parts of a monitoring and surveillance programme on specific prescriptive regulatory

requirements For example monitoring is necessary for comparison with surface water quality

standards which are often established in advance by the regulator Uncertainties in meeting this kind

of regulatory criterion are limited to uncertainties in the measurement methods

86 However regulatory compliance for performance-based criteria such as dose will require

monitoring to provide insights into features events and processes (FEPs) and system performance

which give information to support the safety case and safety assessment Since approaches for

achieving this type of regulatory requirement do not follow strict rules there should be good and early

communication between regulator operator and other interested parties This communication is

needed because the range and type of uncertainties are larger and more subjective than for prescriptive

regulatory requirements The uncertainties are resolved as much by the process by which they are

addressed as by the monitoring data that support the analysis

Use of Monitoring and Surveillance Information in the Safety Case

87 The monitoring and surveillance data collected during the pre-operational period should

include retrospective data from comparable types of facilities if possible The purpose of such data is

to provide confidence in the general approach for disposal being proposed For example comparisons

of the operating records of nearby waste disposal facilities can provide confidence that the technology

is safe and sustainable For near surface and geological disposal facilities for which there may be less

operational history natural or archaeological analogues may assist in fulfilling this function

88 As the facility moves into the operational period monitoring and surveillance should continue

to provide information about operating performance which can be used to update the safety case The

operational safety case is developing prior to obtaining a construction and operation license Residual

uncertainties are often managed using conservative estimates of system functions with respect to their

implications for safety Available monitoring information prior to construction while sufficient to

make a safety case should continue to be updated through the operational stage as part of a performance

confirmation programme This performance confirmation programme should progressively improve

understanding of the system which in turn should be used to improve operating approaches definition

of safety functions facility design and design of the monitoring programme For example monitoring

data on the corrosion rate of a material collected as part of a performance confirmation monitoring

programme may lead to a modification of acceptable inventory limits in a disposal facility Ideally if

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 37: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

33

the operational safety case is based on conservative estimates then changes or improvements in

understanding should lead to less restrictive and less costly operating approaches

89 After the completion of the emplacement operations but before the final closure of the

disposal facility monitoring and surveillance data may be collected to confirm the continuing presence

of safety functions either through direct evidence (ie a measurable parameter) or through the

collection of data that might cast doubt on safety function performance These data may be used to

verify that the disposal system is functioning as expected This means that the components fulfil their

function as identified in the safety case and that actual conditions are consistent with the assumptions

made for safety after closure For example these data may be used to help support the decision for

termination of active institutional controls by verifying that the disposal system has remained in a

passively safe condition for a specified period of time

DEVIATIONS FROM EXPECTED RESULTS

810 As discussed in the previous section the operational safety case is often built on a set of

conservative assumptions to manage the uncertainties at that stage in the facility development

Monitoring and surveillance undertaken for performance confirmation would therefore be expected to

provide data that may be different than that used in the safety case and generally is expected to trend

toward less conservatism Similarly because of the conservatisms incorporated within the safety

assessment environmental monitoring data may be expected to remain within those level forecast

within the safety case However monitoring results may also provide apparent or actual contradictions

such as the appearance of parameters or events not anticipated in the safety assessment Such types of

results could be labelled as lsquounexpectedrsquo as they do not lsquoconfirmrsquo prior expectations

811 Unexpected results do not necessarily indicate that disposal system safety has been

compromised Once possible measurement errors are excluded the information should be analysed

with care to determine its significance within the existing safety case The complexity of the safety

assessment means that comparison with monitoring results may produce counterintuitive results For

instance a conservatively biased groundwater transport model in a safety assessment may neglect or

de-emphasize the leading edge of a contaminant plume Therefore monitoring observations of the

early arrival of contaminants that are inconsistent with the model results may reflect the conservative

bias of the model rather than a failure of the safety case to adequately represent the risk

812 Unexpected results may also be indicative of new information that is not reflected in the safety

case This new information will generally be associated with FEPs that are not well understood or

FEPs that were previously not considered to be of importance If the unexpected results are determined

to fall in this category a revised monitoring andor surveillance programme should be developed to

further investigate the issue and in some cases it may be appropriate to initiate new research to better

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 38: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

34

understand it The safety case should be updated to reflect the new knowledge When unexpected

results occur they may raise questions with the regulator and may influence interested parties

confidence In this regard proper communication transparency and honesty should be emphasized to

maintaining credibility

813 During the period between the decision to go for a waste disposal facility and facility closure

decisions will need to be made about how when and if to license and implement various periods of the

development of the disposal facility system One of the objectives of monitoring and surveillance and

of the analysis of the data is to provide information to assist in making these decisions Decision

making is strongly influenced by societal and political considerations and will be embedded into the

national legal and regulatory system The decision making process should be supported by an adequate

organizational framework and corresponding technical and administrative measures

814 For reasons such as those given in the example above in para 811 failure of performance

criteria would not necessarily imply that remedial actions or protective measures would be needed For

example a decision process for retrieval could be linked to factors where an exposure situation is not

apparent (eg a corrosion indicator) and other factors may be more important to the decision than the

performance indicator (eg safety of workers during retrieval of waste) The mission of a disposal

facility for radioactive waste is to provide for passive safety in the long term Disposal facilities are

designed so that active management in the long term is not required for safety

815 A graded approach should be taken in responding to unexpected results Many issues can be

resolved by an appropriate level of response which may vary from no action at all increased sampling

frequency for confirmation through design or procedural changes all the way to significant remedial

action or even retrieval of wastes Emphasis should be placed on identifying trends rather than

assigning too much significance to individual measurements Actions such as waste retrieval should

only be undertaken after very careful study and justification including consideration of risks

associated with the remedial activity

PERIODIC REVIEW OF THE MONITORING AND SURVEILLANCE PROGRAMME

816 Design of monitoring and surveillance programmes should be an iterative process allowing

for periodic changes to the programmes The safety case and safety assessments are useful tools to be

exploited to review the monitoring and surveillance programmes The monitoring and surveillance

programmes should be designed with flexibility in mind to incorporate new sources of data new

types of data new technologies and new regulatory requirements

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 39: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

35

9 MANAGEMENT SYSTEM

91 The monitoring and surveillance programmes should adhere to the management system

principles established in Refs [17 19] Elements of the management programme that should receive

particular attention with regard to monitoring and surveillance are

bull Ensure the continuity of resources over long time periods

bull Establish processes leading to qualification of the monitoring and surveillance programmes

and data derived from it in the regulatory process

bull Control of records over the duration of the project

92 Monitoring and surveillance systems for waste disposal should be capable of providing data to

support decisions that will occur over the entire lifetime of the facility Since disposal facility lifetimes

are so long it follows that management systems must be established to maintain continuity of data

collection data management and adaptability to new approaches for collection and interpretation of

data Some types of monitoring and surveillance require consistent long-term funding to be useful

and the management system should establish approaches to ensure the continuity For instance many

field experiments may require years before they produce credible and useful data Such experiments

may be important to establishing a credible safety case but they may also be subject to transitory

funding restrictions that can end the experiment too early limiting their worth The management

system should establish provisions to ensure proper planning for financial and qualified human

resources when necessary

93 Management processes are necessary to establish the qualification of data in a regulatory

setting The qualification of data should constitute a set of procedures that permit traceability and

transparency of data and their interpretation when such data are to be used in regulatory decisions

Data used in a safety case may be derived from one of several origins

bull Data collected within the project subject to the management system

bull Data collected as part of a research programme that are not part of the management system

bull Data collected historically which predate the existence of the management system

bull Literature information that reflects general knowledge understanding or measurements not

necessarily specifically associated with the project under consideration

94 The management system should establish clear processes for qualifying each of these types of

information For example to qualify historical data it may be necessary to establish management

processes for review of the original data to ensure it is correct and traceable

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 40: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

36

95 The management system should accommodate data management (record keeping archiving)

over the duration of the project lifetime Since disposal facility programmes have particularly long

lifetimes and since and surveillance data collected throughout the lifetime of the disposal facility will

be needed for decisions taken late in the lifetime there is a particularly stringent requirement on the

management system to provide long-lasting traceability and transparency of monitoring and

surveillance data

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 41: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

37

REFERENCES

[1] EUROPEAN ATOMIC ENERGY COMMUNITY FOOD AND AGRICULTURE

ORGANIZATION OF THE UNITED NATIONS INTERNATIONAL ATOMIC ENERGY

AGENCY INTERNATIONAL LABOUR ORGANIZATION INTERNATIONAL

MARITIME ORGANIZATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN

HEALTH ORGANIZATION UNITED NATIONS ENVIRONMENT PROGRAMME

WORLD HEALTH ORGANIZATION Fundamental Safety Principles IAEA Safety

Standards Series No SF-1 IAEA Vienna (2006)

[2] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-1 IAEA Vienna (1999)

[3] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal of Radioactive

Waste IAEA Safety Standards Series No WS-R-4 IAEA Vienna (2006)

[4] INTERNATIONAL ATOMIC ENERGY AGENCY Disposal of Radioactive Waste IAEA

Safety Standards Series No SSR-5 IAEA Vienna (2011) [DS354]

[5] INTERNATIONAL ATOMIC ENERGY AGENCY Geological Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS334

[6] INTERNATIONAL ATOMIC ENERGY AGENCY Near Surface Disposal Facilities for

Radioactive Waste Safety Guide Draft Safety Standard DS356

[7] INTERNATIONAL ATOMIC ENERGY AGENCY Protection of the public against exposure

to natural sources of radiation including NORM residues Safety Guide Draft Safety Standard

DS421

[8] FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS

INTERNATIONAL ATOMIC ENERGY AGENCY INTERNATIONAL LABOUR

ORGANISATION OECD NUCLEAR ENERGY AGENCY PAN AMERICAN HEALTH

ORGANIZATION WORLD HEALTH ORGANIZATION International Basic Safety

Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources

Safety Series No 115 IAEA Vienna (1996)

[9] INTERNATIONAL ATOMIC ENERGY AGENCY Environmental and Source Monitoring

for Purposes of Radiation Protection IAEA Safety Standards Series No RS-G-18 IAEA

Vienna (2005)

[10] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring and Surveillance of

Residues from the Mining and Milling of Uranium and Thorium IAEA Safety Reports Series

No 27 IAEA Vienna (2002)

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 42: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

38

[11] INTERNATIONAL ATOMIC ENERGY AGENCY Surveillance and Monitoring of Near

Surface Disposal Facilities for Radioactive Waste IAEA Safety Reports Series No 35 IAEA

Vienna (2004)

[12] INTERNATIONAL ATOMIC ENERGY AGENCY Monitoring of Geological Repositories

for High Level Radioactive Waste IAEA-TECDOC-1208 IAEA Vienna (2001)

[13] INTERNATIONAL ATOMIC ENERGY AGENCY Occupational Radiation Protection

IAEA Safety Standards Series No RS-G-11 IAEA Vienna (1999)

[14] INTERNATIONAL ATOMIC ENERGY AGENCY Classification of Radioactive Waste

IAEA Safety Standards Series No GSG-1 IAEA Vienna (2009)

[15] EUROPEAN COMMISSION Thematic Network on the Role of Monitoring in a Phased

Approach to Geological Disposal of Radioactive Waste Final Report European Commission

EUR 21025 EN (2004)

[16] INTERNATIONAL ATOMIC ENERGY AGENCY Preparedness and Response for a

Nuclear or Radiological Emergency IAEA Safety Standards Series No GS-R-2 IAEA

Vienna (2002)

[17] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for the

Disposal of Radioactive Waste IAEA Safety Standards Series No GS-G-34 IAEA Vienna

(2008)

[18] INTERNATIONAL ATOMIC ENERGY AGENCY Programmes and Systems for Source

and Environmental Radiation Monitoring IAEA Safety Reports Series No 64 IAEA Vienna

(2010)

[19] INTERNATIONAL ATOMIC ENERGY AGENCY The Management System for Facilities

and Activities IAEA Safety Standards Series No GS-R-3 IAEA Vienna (2006)

[20] INTERNATIONAL ATOMIC ENERGY AGENCY Borehole Disposal Facilities for

Radioactive Waste IAEA Safety Standards Series No SSG-1 IAEA Vienna (2009)

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 43: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

39

Annex I

EXAMPLE OF MONITORING AND SURVEILLANCE INFORMATION COLLECTED

FOR A GEOLOGICAL DISPOSAL PROGRAMME

I-1 As described in [12] parameters to be monitored in a radioactive waste disposal can be

separated into different categories

bull Baseline

bull Behaviour of the waste package and its associated buffer material

bull Degradation of disposal facility structures and engineered barriers

bull Near field chemical and physical disturbances induced by the construction of the disposal

facility and the interactions between introduced materials groundwater and host rock

bull Chemical and physical changes to the surrounding geosphere and in the atmosphere

bull Radionuclide release detection

bull Provision of an environmental database

Baseline

I-2 Certain monitoring activities are expected to begin at the earliest possible time within a

disposal facility development programme before the perturbations caused by disposal facility

construction and operation begin to accumulate This early information is important because it allows

an understanding to be developed of the nature and properties of the natural lsquoundisturbedrsquo

environment of the disposal system

I-3 Baseline monitoring is concerned with the initial values of parameters that will continue to be

monitored by either continuous or periodic observations The scope of baseline monitoring includes

the determination of conditions and parameters of potential interest for basic earth science

engineering and the environment and the operational and post-closure safety assessment of the

disposal facility The scope of this monitoring needs to be sufficiently broad to allow issues not

foreseen today to be considered in the future [15] For example it will be used to evaluate changes that

occur in the rock and groundwater system during the construction and operational periods and in the

post-closure stage to evaluate any impacts that the presence of the disposal facility may have on

natural processes and the environment In practice the monitoring programme will begin during the

site investigation stage

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 44: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

40

I-4 The characteristics of primary interest in the context of establishing baseline information are

bull The groundwater flow field in the host rock and in the surrounding geological environment

(groundwater pressure distributions hydraulic gradients regions of recharge and discharge

etc)

bull Geochemical characteristics of groundwater (redox salinity major and trace element

concentrations natural radionuclide content etc)

bull Mineralogy of the host-rock making part of the disposal facility system

bull Geomechanical properties of the host-rock participating to the stability of the disposal facility

structure

bull Retention properties amp hydraulic properties of the host-rock making part of the disposal

facility system

bull Characterization of the discontinuities (including fractures) of the host-rock making part of the

disposal facility system

bull Background levels of natural radioactivity in groundwater surface waters air soils and

sediments animal and plant life

bull Meteorological and climatic conditions

bull Hydrology of surface water systems including drainage patterns and infiltration rates

bull Ecology of natural habitats and ecosystems

I-5 Baseline data needs to be established as part of the site characterization activity eg

measurements from local and regional boreholes and surface investigations Where important

parameter values are found to follow an increasing or decreasing trend baseline monitoring will need

to be continued until that trend is established with confidence and the reasons for the trend are

sufficiently well understood The establishment of baseline values for surface environmental indicators

is relatively straightforward because the process of measurement will in general not affect the

parameters being measured (eg measurements relating to climatic factors and surface hydrology)

However it is to be appreciated that invasive investigations will themselves perturb the natural

groundwater system to a degree based on site specific conditions In order to establish baseline

conditions with which to judge later impacts eg changes to groundwater pressures and

hydrochemical conditions in response to disposal facility construction sufficient information needs to

be collected in the surface exploration stage to have confidence that the undisturbed conditions have

been adequately characterized both spatially and temporally

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 45: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

41

Monitoring conditions of emplaced waste packages

I-6 Waste package conditions are relevant to waste retrievability and monitoring of parameters

that indicate the integrity or the status of waste packages would be particularly important The

behaviour of emplaced waste packages will depend upon degradation phenomena such as corrosion

and effects such as waste stack stability resaturation (eg of buffer and waste) and gas production

I-7 The parameters that could be monitored for use as indicators of the condition of waste

packages fall into two categories direct measurements (eg corrosion current strain swelling pressure

for clay buffers) and environmental measurements (eg temperature humidity resaturation pressure)

In some disposal facility designs particularly for low and intermediate level waste the analysis of

waste-derived gases as close as possible to the waste packages may provide useful indications about

their integrity andor about the performance of already emplaced engineered barriers

Monitoring of the disposal facility structures and engineered barriers

I-8 Changes in the structural stability of disposal facility may occur as a result of natural

processes and human activity Continuing monitoring of the surrounding area may contribute to assess

its stability and to detect any movement of the disposal facility structure or the surrounding host rock

I-9 The parameters that could be monitored are

- Mechanical properties

- Stresses

- Strain

- Conventional observation of underground openings

- Rock stresses

- Deformations and loads on rock supports

- Deformations in walls and lining

- Fractures

I-10 The engineered barriers comprise all the materials placed around the waste to isolate and

contain it including any low permeability or intrusion resistant components Engineered barriers

include backfills and seals and in some cases parts of the disposal facility structure

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 46: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

42

Disturbances created by the disposal facility

I-11 The construction of a disposal facility will disturb the pre-existing natural system The

subsequent stage of disposal facility operations will cause further changes Some of these changes may

take many years to manifest themselves Therefore an important aspect of the monitoring programme

will be concerned with changes to the disposal facility environment resulting from effects such as

bull Mechanical disturbance as a result of the excavation activities

bull Hydraulic and hydrochemical disturbances resulting from excavation and drainage

bull Thermo-mechanical effects caused by the emplacement of heat-producing waste

bull Geochemical disturbance due to chemical reactions caused by the disposal facility

construction and operation (primarily the introduction of air but also of backfill materials for

strengthening like groutsshotcrete seal materials and of the waste itself)

I-12 The parameters that could be monitored in the engineered barriers are

- Mechanical disturbance in the host rock

- Stress field

- Deformation

- Fractures

- Hydraulic disturbance

- Permeability

- Water pressure

- Saturation degree

- Geo-chemical disturbances

- Composition (interstitial water + mineralogy)

- pH

- Redox

- Retention properties

- Biological changes

- Thermal disturbances

- Temperature distribution

- Conductivity

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 47: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

43

Monitoring of radionuclide release

I-13 The following parameters measured through the engineered barriers the host-rock and the

geosphere can provide information on the potential for mobilization and release of contaminants

- Leachate monitoring

- Activity concentration in ground water

- Extent of the potentially contaminated zone

- The hydraulic gradients and the velocity and direction of the flow in the potentially

contaminated zone

- The level of the water table

- River flow rate (which could influence the hydrological conditions)

- Recharge of aquifer

- The chemical composition of the water

Changes to the geosphere

I-14 The geosphere surrounding a disposal facility will respond in a number of different ways to

the presence of the disposal facility (eg mechanically hydraulically chemically) Relevant

measurable parameters are temperature stress groundwater chemistry groundwater pressure solute

chemistry and mineralogy These parameters will often be measurable using boreholes drilled during

the site characterization and underground investigation phases Many mineralogical changes in

response to disposal facility ventilation are likely to be confined to the immediate vicinity of the

disposal facility

I-15 Of particular interest are changes to the hydraulic and mechanical behaviour of rock structures

that may have a direct bearing on the long term performance of the isolation system eg the

connectivity of major water conducting fractures Again investigation of these features is likely to be

by boreholes drilled during the site characterization and underground investigation phases

I-16 For disposal facilities in the saturated zone groundwater will flow around or through the

disposal facility while the disposal facility remains open However following disposal facility

resaturation (or perhaps resaturation of part of the disposal facility) groundwater will flow through the

disposal facility back into the geosphere This will produce geochemical changes in the geosphere For

some disposal facility concepts eg those that make extensive use of cement the changes may be

profound

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 48: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

44

Accumulation of an environmental database

I-17 The accumulation of environmental data over a period of several decades may be of great

assistance in assessing the suitability of the land above a disposal facility for alternative land uses

I-18 Parameters of potential relevance are

bull Meteorology

bull Hydrology drainage water usage water quality

bull Concentration of radionuclides and other pollutants in various environmental compartments

including biota sediments and waters

bull Local ecology

bull Geomorphological processes such as denudation localized erosion slope evolution

bull Tectonic activity such as vertical and lateral earth movement rates seismic events geothermal

heat flow

bull Land use in the surrounding region

I-19 All these parameters may be measured from the surface The data is expected to be continuous

and extend over many years

I-20 If no method can be identified that respects all monitoring constraints alternative strategies

will have to be used The option of constructing within the confines of the disposal facility or nearby

in the same host rock an extensively instrumented demonstration or lsquopilotrsquo facility avoiding thus any

breaching of the real isolation barriers could be evaluated Logically this demonstration would take

place before the authorization of disposal facility operations however in some geological disposal

programmes the continuation of demonstration and thus the associated monitoring concurrently with

disposal operations in the disposal facility has been suggested One anticipated advantage of such

strategy would be to provide additional confirmation of the reliability of assumptions about overall

system performance

Table I-1 below describes the importance of the different monitoring parameters during the different

periods of development of a geological disposal facility

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 49: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

45

TABLE I-1 PARAMETERS TO BE MONITORED DURING VARIOUS PERIODS OF

DEVELOPMENT OF A GEOLOGICAL DISPOSAL FACILITY

Parametersprocess to be monitored Pre-operational Operational Post-closure1

BASELINE (INITIAL VALUE)

Groundwater flow field in the host-rock and the surrounding

geosphere

- groundwater pressure distributions

- hydraulic gradients

- flow directions

- permeabilities

- regions of recharge and discharge

X

Geochemical characteristics of ground water

- redox

- salinity

- major and trace element concentrations

- natural radionuclide content background activity

X

Mineralogy of the host-rock making part of the disposal facility

system X

Geomechanical properties of the host-rock participating to the

stability of the disposal facility structure X

Retention properties amp hydraulic properties of the host-rock

making part of the disposal facility system X

Characterization of the discontinuities (including fractures) of the

host-rock making part of the disposal facility system X

Background levels of natural radioactivity in groundwater surface

waters air soils and sediments animal and plant life X

Meteorological and climatic conditions X

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 50: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

46

Parametersprocess to be monitored Pre-operational Operational Post-closure1

Hydrology of surface water systems including drainage patterns

and infiltration rates X

Ecology of natural habitats and ecosystems X

Mechanical properties of the disposal facility structure X

Mechanical properties of the engineered barriers X

Retention amp hydraulic properties of the engineered barrier X

CONTINUED MONITORING OF BASELINE

PARAMETERS X X

INTEGRITY OF WASTE PACKAGES

Direct measurement

- corrosion

- strain

- pressure on the waste package (ie swelling pressure for

clay buffer)

X (X)

Environmental measurements

- temperature

- humidity

- resaturation

- analysis of waste derived gases

X (X)

DISPOSAL FACILITY STRUCTURES AND ENGINEERED

BARRIERS

Structural stability of disposal facility structure and engineered

barrier

- mechanical properties

X (X)

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 51: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

47

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- stresses

- strain

- conventional observation of underground openings

- rock stresses

- deformations and loads on rock supports

- deformations in walls and lining

- fractures

Behaviour of engineered barrier (ie backfill and seal)

- resaturation rate

- changes in

- hydraulic properties

- mechanical properties (including swelling)

- chemical properties

- thermal properties

X (X)

Prevent water ingress into the disposal facility - water infiltration

through the disposal facility X (X)

DISTURBANCES CREATED BY THE DISPOSAL

FACILITY (CONSTRUCTION EMPLACEMENT OF

WASTE AND ENGINEERED BARRIERS hellip)

mechanical disturbance in the host rock

- stress field

- deformation

- fractures

X (X)

geo-chemical disturbances

- composition (interstitial water + mineralogy)

- PH

- redox

X (X)

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 52: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

48

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- retention properties

- biological changes

hydraulic disturbance

- permeability

- water pressure

- saturation degree

X (X)

thermal disturbances

- temperature distribution

- conductivity

X (X)

Monitoring of radionuclide release

Leachate monitoring X (X)

Activity concentration in ground water X X

Extent of the potentially contaminated zone X X

Hydraulic gradients velocity and direction of the flow in the

potentially contaminated zone X X

The level of water table X X

Rechargedischarge of aquifer X X

Chemical composition of water X X

Changes to geosphere

Mechanical

- stresses X X

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 53: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

49

Parametersprocess to be monitored Pre-operational Operational Post-closure1

- strain

- fractures (connectivity which could create preferential

pathway)

Hydraulic

- ground water pressure X X

Chemical

- solute chemistry

- mineralogy

X X

Thermal

- temperature X X

ACCUMULATION OF AN ENVIRONMENTAL

DATABASE

Meteorology X X X

Hydrology drainage water usage water quality X X X

concentration of radionuclides and other pollutants in various

environmental compartments including biota sediments and

waters

X X X

local ecology X X X

geomorphological processes such as denudation localized

erosion slope evolution X X X

tectonic activity such as vertical and lateral earth movement rates

seismic events geothermal heat flow X X X

land use in the surrounding region X X X

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 54: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

50

1 Parameters measured during the operational phase may continue to be monitored during the post-closure phase but to a less

extent as long as it will not affect the long term safety

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 55: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

51

Annex II

EXAMPLE OF MONITORING AND SURVEILLANCE PROGRAMME FO R A

NEAR SURFACE DISPOSAL PROGRAMME

HUNGARY ENGINEERED DISPOSAL FACILITY AT PUumlSPOumlKSZIL AacuteGY

INTRODUCTION

II-1 The Radioactive Waste Treatment and Disposal Facility (RWTDF) have been operated by

Hungarian national radioactive waste management company (PURAM) since July 1998 Earlier it was

operated by National Health Public Officers Service since 1976 when the site was commissioned The

task of the facility is to accommodate the low- and intermediate level institutional radioactive waste

arisen in Hungary from small-scale producers

II-2 The site is located some on the ridge of a hill at an altitude of 200-250 m above Baltic Sea

level laying on approximately 30 m thick heterogeneous Quaternary rocks (silt and clay low

permeability) above the ground water table It is bounded to SW by the Nemedi and to NE by the

Szilagyi stream The facility is 15 km far from the nearest village (Puumlspoumlkszilaacutegy)

II-3 The layout of the facility monitoring system is shown in Figure II-1

II-4 The installation is a Radon type near surface disposal facility Reinforced concrete storage

vault (Type A and C) and carbon steelstainless steel storage wells (Type B and D) are provided for

the disposal of radioactive wastes in RWTDF

II-5 ldquoArdquo type system which is a reinforced concrete structure (40 cm thick walls) serves for

disposal of solid radioactive waste There are four vaults (AI - AIV) each vault consists of cells of 70

m3 each It is covered by protective roof during the filling then sealed and temporarily covered by 2 m

thick clay layer Final cover is still to be designed

II-6 ldquoCrdquo type disposal system serves for storage of solidified organic solvents and biological

waste but it is recently used for temporary storage of neutron sources It consists of 8 cells of 15 m3

each and is covered by protective roof

II-7 ldquoBrdquo type system serves for storage of disused sealed sources (DSRS) There are 16 wells with

a diameter of 40 mm and 16 wells with a diameter of 100 mm (6 m depth) is located inside a concrete

monolith structure

II-8 ldquoDrdquo type system serves for storage of DSRS with a half-life greater than 30 years (226Ra 241Am) It consists of 4 wells with a diameter of 200 mm and 16 wells with a diameter of 100 mm

(steel lined and 6 m depth)

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 56: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

52

PRE-OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-9 Between 1974-1976 before the disposal facility start the operations reference levels (ie

background values prior to the operation) were identified for the most significant points of the

environments (along the water courses and in the ground water) around the disposal facility

II-10 Sampling points were determined in the village nearby along the two brooks flowing around

the hosting hill on the slopes of the hill and in the territory of facility

II-11 Monitoring included 137Cs measurement the total gamma- and the total beta activity-

concentration in different environmental samples

minus Soil

minus Air

minus Plants

minus Animals

minus Water

Nemedi brook

Rainwater dike

Fishpond

Settlement

Treatment amp Storage Disposal

units

Settlement

Settlement

Settlement

Settlement

Szilagyi brook

Galga brook

Road

Road

Road

FIG II-1 Layout of RWTDF monitoring system Only the most important sampling points are illustrated Not to scale

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 57: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

53

Indash3 EARLY OPERATIONAL MONITORING AND SURVEILLANCE ACTIVITIES

II-12 In the first stage of the disposal facility operation the monitoring programme consisted of

sampling in

bull 10 groundwater monitoring wells (water)

bull 8 points along surface water flows (water and sediment)

bull In the rainwater collector (water and sediment)

bull At 6 points for vegetation sampling

bull At two places for aerosol and fall-out

bull At two places for food samples (fish and milk)

II-13 In 1991 the site was extended from 3360 m3 to 5040 m3 In accordance with it an extended

monitoring system was implemented

bull Hydrogeological (underground water) monitoring additional 18 wells were constructed and in

total 28 wells has been used for monitoring of changes of groundwater table level

bull Surface monitoring system (4 fixed measurement point)

bull Near surface radiation monitoring (16 wells each of 7 m depth around the disposal vaults to

monitor the radiation of gamma-emitting isotopes in the soil)

bull Isotope-hydrology measurement 3H 14C 90Sr and chemical composition in the groundwater

and in the surface waters

bull Water flow measurements in two cross section along both brooks

bull Involving the new rainwater collector basin

II-14 The basic levels were calculated using 2-year average of data collected (1990-1991)

II-15 The new results were built in the operational monitoring programme

II-16 The first safety evaluation of the system was performed in 1995 and parallel with it a

meteorological system was located aiming at collecting further input data

Indash4 OPERATIONAL MONITORING AND SURVEILLANCE

II-17 The radiological monitoring programme is broadly similar to the pre-operational but sampling

frequencies are generally reduced Based on periodic review of the results and on new

recommendations for sampling and measurement procedures there were some changes in the sampling

frequencies in the range of nuclides measured and the monitoring wells used

54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

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54

II-18 The sampling operations required for the measurements extend over the entire area of the site

and for water courses within a perimeter of 20 km

II-19 The first comprehensive safety assessment was performed in 2000 which was based on the

geological investigations carried out in the 70rsquos and the monitoring data collected 1976-2000 Some

concerns were raised related to the slope stability as a result of the safety assessment therefore erosion

investigation of the slopes was introduced in the monitoring programme

II-20 Later during the re-licensing process of the site the regulatory body requested further

geological investigations which were performed between in 2006-2007

II-21 In 2000 elevated tritium concentration were measured in a few groundwater monitoring wells

Although it has had no impact on the local populationrsquos exposure 6 monitoring wells for continuos

monitoring have been implemented to make detailed investigations in addition to the operational

ones The source and main pathways of the tritium were identified and has been further monitored

II-22 In 2004 following the refurbishment of the treatment and storage building new aerosol and

soil sampling points were installed

II-23 During normal operation of the facility airborne or liquid radioactive discharge may only

occur from the operations building and the storage building both situated within the controlled zone

The generated small amount of liquid waste is stored in sealed tanks no discharge from these thanks

occurred during these years

II-24 The airborne discharge monitoring is carried out by emission measurements with the use of a

sampling unit installed into the ventilation stack Under normal operational conditions the discharge is

minimal and cannot be distinguished from the background values The discharge from the storage

building and the operational building is also monitored by monitoring devices installed in different

locations along the prevailing wind direction

II-25 The environment monitoring operations of the facility are composed of work of several

laboratories The most essential basic measurements are carried out by the internal laboratory of

RWTDF The special measurements and the detection of difficult to measure isotopes in the

environmental samples are undertaken by Hungarian laboratories Vegetation animal soil

sedimentmud aerosol fall-out surface water and ground water samples are collected on regular basis

typically from 40 different sampling locations by the environment monitoring laboratory of the facility

for the purpose of gamma-spectrometry measurement and total beta counting

II-26 Samples are also taken from additional 30 ground water monitoring wells The highly-

sensitive measurements of the vegetation soil and animal samples taken in the direct vicinity of the

facility are analysed by external institution

II-27 The data of the monitoring system are compared to the reference levels identified in 1976 ndash77

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 59: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

55

II-28 Nearly 600 samples are taken annually from the surroundings of the facility The results of

nearly one thousand tests did not show any detectable deviation from the natural background values

This fact was also confirmed by control tests undertaken by competent authorities and independent

institutes

II-29 The gathered radiological information in the surroundings of the facility are recorded in a

computer based national database

II-30 The summary of the monitoring system is showed in Table II-1

TABLE II-1 SUMMARY OF MONITORING SYSTEM

Media

sampled Place

Type of

monitoring Sampling method Measurement Evaluation

Air

in the centre of

the nearest

village environmental

air-filter changed

weekly

fall-out sampling

basin

gross beta amp gamma-

spectrometry base level

Air

at the down-wind

side of disposal

area

environmental

source

air-filter changed

weekly

fall-out sampling

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

every 2 months

gross beta amp gamma-

spectrometry gross

alphabeta

gross beta amp gamma

spectrometry

tritium radiocarbon 90Sr base level

Air

at the down-wind

side of the

treatment-

storage building

100m

environmental

source

filter tape

periodically

forwarded

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross alphabeta

tritium radiocarbon 90Sr base level

Air

in the ventilation

chimney of the

treatment-storage

building source

air-filter changed

weekly

adsorption of 3H on

silica gel and 14C in

barium hydroxide

gross beta amp gamma-

spectrometry

tritium radiocarbon 90Sr discharge limit

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

Page 60: G20110245/EDATS: OEDO-2011-0255- Response Email Re: Action: … · 2012. 12. 5. · Attachments: USA Comments on IAEA Draft Guide DS 357 Boby Eid 08-16-2011 Semi Final.doc Ticket#G20110245

56

every 2 months

Air

in the basement

and the 1st floor

in treatment and

storage building source

filter tape

periodically

forwarded

continous

measurement of l alpha

and beta aerosol

concentration

radiation protection

limits

Surface water

brook-1 upstream

in the centre of

the nearest

village environmental

hand sampling half a

year

gamma- spectrometry

gross beta 3H base level

Surface water

brook-1 upstream

to the site source

hand sampling and

pumping half a year

gross beta amp gamma-

spectrometry tritium

radiocarbon 90Sr ICP base level

Surface water

brook-1

downstream to

the site environmental

hand sampling half a

year

gross beta amp gamma-

spectrometry tritium base level

Surface water

fishpond along

brook-1 environmental hand sampling a year

gross beta amp gamma-

spectrometry base level

Surface water

brook-2 upstream

in the centre of

the nearest

village environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2 upstream

to the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

brook-2

downstream to

the site environmental

the same like brook-

1 the same like brook-1 base level

Surface water

before and after

water collection

river environmental

hand sampling once

a year

gross beta amp gamma-

spectrometry base level

Surface water

20 km along the

water collection

river environmental

hand sampling a

once year

gross beta amp gamma-

spectrometry base level

Rain water

rainwater

collection basin

90 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry

tritium radiocarbon discharge limit

57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

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57

3H

Rain water

rainwater

collection basin

60 m3 (control

zone) source

hand sampling when

the basin is filled

gross beta amp gamma-

spectrometry discharge limit

Ground water

on the slopes

around the site

(23 wells) environment

hand sampling and

pumping half a year

3H 14C gorss beta

gamma spectrometry 90Sr ICP base level

Ground water

inside facility (10

wells) source

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

on the ridge

upward

(background) (3

wells)

environment

(background)

hand sampling and

pumping half a year

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Ground water

in control zone (6

wells) source

hand sampling and

pumping monthly for 3H half a year for

others

3H 14C gorss beta

gamma- spectrometry 90Sr ICP base level

Sediments along the springs environmental

sampling the mad

from the water

without benthos

gorss beta gamma-

spectrometry base level

Soil

Inside the site

(11 places) source

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Soil

inside the site (6

places) source

hand sampling once

a year

90Sr gorss beta

gamma- spectrometry base level

Soil

outside of the site

(4 places) environmental

hand sampling once

a year

gorss beta gamma-

spectrometry base level

Plant along the springs environmental

hand sampling half a

year

gorss beta gamma

spectrometry base level

Plant

inside the site (5

places) environmental

hand sampling half a

year

gorss beta gamma-

spectrometry 90Sr base level

Animal from the lake environmental sampling the whole

fishes only native gorss beta gamma- base level

58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

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58

fishes half a year spectrometry 90Sr

Animal inside the site environmental

sheeps at the site

once a year

gorss beta gamma

spectrometry 90Sr base level

Hydroge-

ology 26 wells environmental

measurements by

hand devices twice a

year

level of the water

surface in the wells base level

Hydroge-

ology 8 wells environmental

installed detectors

continuously

level of the water

surface in the wells base level

Hydroge-

ology

2 cross-section

on both brooks environmental

measurements by

hand devices half a

year

monitor the runoff of

the brooks upstream

and downstream to the

site base level

Radiation in-situ at 6 places environmental once a year

In-situ gamma-

spectrometry

base level

Radiation

dose rate meters

at the disposal

(7) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Radiation

dose rate meters

in the building

(23) source

installed detectors

continuously

continuous gamma

dose rate measurement

radiation protection

limits

Meteorology

next to the

disposal vaults environmental

automatic

meteorology station

wind temperature

vapour precipitation -

Geodesy

4 fixed

measurement

points environmental

measurements by

hand devices

monitoring of the earth

surface monitor the

moving of the surface base level

Erosion on the slopes environmental

installed detectors

continuous

measurement

monitoring the amount

of rain and the eroded

soil -

Drainage

below the

disposal vaults surveillance

hand sampling the

water half a year

tritium gamma-

spectrometry

-

PLANS FOR POST-OPERATIONAL MONITORING

59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

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59

II-31 At present the post-operational monitoring requirements are not well defined Eventually they

will be specified by the regulatory body with due consideration being given to the physical biological

and geochemical features of the disposal site and surrounding area

60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency

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60

CONTRIBUTORS TO DRAFTING AND REVIEW

Berkovskyy V International Atomic Energy Agency

Bernier F

Bruno G

Federal Agency for Nuclear Control (FANCAFCN)

Belgium

International Atomic Energy Agency

Dupuis C Institut de radioprotection et de sucircreteacute nucleacuteaire (IRSN)

France

Hioki K

Jova Sed L

Japan Atomic Energy Agency (JAEA) Japan

International Atomic Energy Agency

Killey RWD Atomic Energy of Canada Limited Canada

Kozak MW Monitoring Scientific LLC United States of America

Lush D EcoMetrix Inc Canada

Mayer S Agence nationale pour la gestion des deacutechets radioactifs

(ANDRA) France

McEwen T T McEwen Consulting United Kingdom

Rendell P Nuclear Decommissioning Authority United Kingdom

Rowat JH International Atomic Energy Agency