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Directorate General National Repository

Pakistan Atomic Energy Commission

PAEC-IAEA National Workshop on Strategy and Methodologies for the Development of Near Surface Disposal Facilities

February 24-28, 2014, Islamabad

CURRENT STATUS OF NEAR SURFACE DISPOSAL PROGRAM IN PAKISTAN

Masood Akhter Deputy Chief Scientist

CONTENTS

Pakistan – An introduction Repository development program General site selection criteria Potential rocks/sites identification Summary

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Pakistan – An Introduction

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Pakistan

Pakistan is situated in South Asian region between latitudes 24º & 37º N & longitudes 61º & 76º E, covering a total land area of 796,095 sq. km.

Pakistan may be divided into four geographic regions

The plateau of W Pakistan

The plains of the Indus and Punjab rivers

The hills of NW Pakistan

The mountains of N Pakistan

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Pakistan (continued)

Himalayas, Hindukush and Karakuram mountain Ranges meet in the Northern Pakistan.

In rest of the country there is a belt of sub-mountain Potwar plateau and Salt range, western bordering highlands the Balochistan plateau and southern Indus plain.

The country shares its borders with Iran to the West, India in the Southeast, Afghanistan in the Northwest, and China in the North.

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Pakistan (continued)

The country has a generally hot and dry climate, with desert conditions prevailing throughout much of the area

The Indus is the chief river of Pakistan and is the nation's lifeline. It flows the length of the country and is fed by the combined waters of three rivers i.e Chenab, Jhelum, and Ravi.

Along the Indus and its tributaries are found most of Pakistan's population, its chief agricultural areas, and its major hydroelectric power stations.

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Pakistan (continued)

The Pakistan region comprises diverse nature of geological features as it lies at the junction of Indian, Eurasian and Arabian plate boundaries

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Major tectonic trends on and around the northwest part

of the Indo-Pakistan subcontinents

Disposal

WHAT IS DISPOSAL?

Emplacement of radioactive waste in a disposal

system (repository):-

• with reasonable assurance for safety

• without the intention of retrieval

• without reliance on long-term surveillance and maintenance

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Objective

To isolate radioactive waste from the

biosphere for a long period of time to

protect human health, environment now and

in the future without imposing undue

burdens on future generations

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Disposal Facilities Development

Program

Development of a disposal facility is a big task

International waste disposal programmes reveals that granite, salt and clay formations act as favorable hosts

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There are three phases associated with the lifetime of a disposal facility which are;

Pre-operational

Operational

Closure & Post-closure

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The pre-operational phase includes the necessary siting studies

Siting of radioactive waste disposal facilities is an important step in developing a waste disposal system that would best suit the needs for accommodation of wastes from a national nuclear programme and simultaneously satisfy all relevant safety, technical and environmental requirements set out in various national and international guidelines

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Siting Process for Near Surface

Disposal Facility

The set of all activities (up to construction of disposal facility) towards development of disposal facilities/repositories is termed as siting-process

Siting process is a step-by-step activity and following are the main stages;

Conceptual & planning stage

Area survey stage

Site characterization stage

Site conformation stage

Suitable disposal sites are selected against predefined siting criteria

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Site Selection Criteria There are general guidelines that govern the site

selection criteria, mainly from the viewpoint of safety, while non-safety related considerations are also necessary and these include social and economic impacts

Exclusion criteria

Exclusion criteria have to be selected taking into account of several geographical, environmental, socio-economic, sociopolitical and technical constraints

Site(s) falling in exclusion criteria should not be considered for further work

The exclusion criteria is based taking into account of both technical and non technical attributes

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Site Selection Criteria

Technical attributes:

Natural resources; Significant natural resources, including

ground water

Seismic hazard; History & probability of surface/ground

rupture or permanent ground displacement

Volcanic activity; Quaternary or any expected future volcanism

Nontechnical attributes:

Population; Heavy population density

Agriculture; Lot of potential for agriculture

Environment; Notable ecological significance or habitat of

rare fauna/flora

Heritage; Special culture or historical significance

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Site Selection Criteria

Apart from the exclusion criteria following are the basis which should be considered for the establishment of Site Selection Criteria

Technical attributes:

Geology; rock type, rock mass, dip & strike of strata etc.

Geotectonic; faults, folds, fractures etc.

Geomorphology; slopes/relief, soil, drainage pattern etc.

Hydrogeology; surface & ground water, flooding etc.

Seismicity; seismic hazard analysis, seismogenic structures etc.

Climate; temperature, wind speed/direction, humidity etc.

Rainfall; precipitation, evaporation etc.

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Site Selection Criteria

Nontechnical attributes: Land-use

Population distribution and density

Accessibility

Utility/services

Security & political condition

Land ownership

Distance from international borders

Distance from load centers

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Disposal Facility - Pakistan

Almost 90% of radioactive waste produced in Pakistan fall in LILW-SL category and mostly contain short lived radionuclides and low concentrations of long lived radionuclides

Such type of wastes is suitable for disposal in Near Surface Disposal Facility (NSDF)

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Status of Disposal Facilities in Pakistan

Activity Near Surface

Disposal Facility

Deep Geological

Repository

Siting Process In-progress Planning

Facility Development

- -

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Near Surface Disposal Facilities

(NSDF)

Near-surface disposal facilities are facilities located at the surface of the ground or at depths down to several tens of meters below the surface

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NSDF

Suitable for short lived LILW that contains mainly

radionuclide which decay to radiologically insignificant levels within a few decades or centuries

LILW that contains limited concentrations of long lived radionuclide may also be suitable for near surface disposal

In NSDF, active controls in the form of continuous monitoring and surveillance provide additional safety measures and contribute to confidence in the satisfactory performance of the facility

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NSDF

All NSDF concepts rely on a system of passive barriers (multi-barrier concept) to prevent, or very drastically delay, the transport of radionuclides into the biosphere

The barriers are combination of engineered and natural barriers

Isolation from the biosphere is provided by placing several barriers between the waste materials and the external environment, arranged in succession so that each barrier reinforces the preceding one

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Near Surface Disposal Facilities at

Ground Level

These facilities are on or below the surface

where the protective covering is of the order of a

few meters thick

Waste containers are placed in constructed

vaults and when full the vaults are backfilled

Eventually the vaults will be covered and capped

with an impermeable membrane and topsoil

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Near Surface Disposal Facilities in

Caverns Below Ground Level

These facilities require under ground excavation of caverns conducted from surface

Such facilities are at a depth of several tens of meters below the earth's surface and accessed through a drift

Near surface disposal facilities are typically used for LLW and ILW with a radionuclide content of short half-life (up to about 30 years)

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Engineered, NSDF

Typically capacity thousands of cubic meter

Ease of waste emplacement

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NSDF - Pakistan

All kinds of rocks (e.g. sedimentary, metamorphic and igneous) are present in the stratigraphic sequence of Pakistan

Due to unstable political as well seismo-tectonic conditions we have to focus on risk-free or least venturous regions of the country

In conceptual planning stage, 39 sites/formations from the stratigraphic sequence of Pakistan were studied for evaluation of their initial potential for the disposal of various type of radioactive waste

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Initially survey of 11 sites/areas in Chakwal, Mianwali & DG Khan regions have been completed

Detail site characterization studies at Dhok Miani-Nara Site is in progress

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To Sakesar

To Mianwali

To Talagang

LAWA

38 P/14

N

East of Dhok Miani Area,Distt.Chakwal,

Grid reference; N 32° 36' & E 71° 54' (38-P/14)

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Dhok Miani-Nara Area,Distt.Chakwal,

Main Features

• Population is relatively low.

• Site is close to load centers.

• Ground water table is quite deep.

• Insignificant mineral potential.

• Area is almost 20 km away from main Talagang - Mianwali

Road

• Suitable for vault type structure.

• Formations are Chinji F. (mainly clay) & Murree/Kamlial F.

(Sandstone/shale sequence).

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NSDF – Pakistan

Modular, Vault type surface disposal facility- under consideration

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Planning for proposed NSDF

Facility will be used for disposal of solid and solidified LILW-SL

Facility will be built in tectonically stable/safe area

Facility will be designed well above the level of water table in order to provide protection from ground water infiltration, with the provision of impermeable base & walls (concrete)

Facility will be built outside the range of any possible flooding & higher than any level possible reached by the water table

Facility will remain under institutional control during the surveillance period and repair can be made if necessary

Intentional human intrusion will be precluded

Isolation of waste from plants, animals and erosive forces will be determined by the quality of engineered barriers and site characteristics

NSDF – Pakistan

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NSDF – Pakistan

The waste packages will be disposed in the vaults & then stabilized by gravels/concrete

Every Vault will be provided with mobile roof / shelter with the provision of crane for remote handling of waste, during operational period

Once full, vaults will be back filled, covered & coated with water proof material that will serve as temporary cover until the final capping

Areas among the vaults will be backfilled with suitable material

After the closure of facility/repository a final cover (capping) will be placed on it, made of a layer of clay, a bituminous membrane & a layer of draining material such as sand

At the end of period of institutional control, the potential radiological risk of the disposal system has become small enough to allow abandonment

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Procedure

Proposed waste disposal procedure at NSDF

NSDF will receive LILW-SL, NPPs waste in

immobilized/over-packed in specially designed (according

to WAC requirement) RCC boxes or barrels

Interim storage

Disposal in NSDF

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1100

900

100

100

13mm Ø C/C 150mm

13mm Ø C/C 100mm

1- M.S Liner 2mm thick

2- 1:2:4 Baryte concrete

3- 13mm Ø M.S bars for R.C.C

4- 25.4mm Ø M.S bolt for lifting

1400

1300

IndexDate M o d i f i c a t i o n s

07-08-09

RCC CONCRETE BARREL

(WMD-SC-RCC-T200)

Designed by:

Mian Ahmad Syed, SEChecked by:

M. Aslam Nasir, PEApproved by:

Drawn by:

Mian Ahmad Syed, SE

Unit:

Scale: 1:12.5

DC-03-1024WMDWASTE MANAGEMENT DIVISION

WMD/ CAD /

TITLE

DWG. NO.

Format:

Folio:

REF.

Remarks

LEGEND

12

34

RCC CONCRETE BARREL

TOP VIEWS

CONCRETE DETAILSREINFORCEMENT DETAILS AA

A

DETAIL B

B

ISOMETRIC VIEW150

Ø1100

Ø1000

Ø80

0

Ø70

0

200

700

150

M 24

S.No Description Details

1 1:2:4Concrete Ratio

2

3

4

5

6

7

9

8

Water cement ratio 0.53

M.S. Reinforcemant

M.S Liner

Volume of Concrete

Empty Weight (Ton)

0.123 Ton

0.048 Ton

815 L

2.70 to 2.80

Tolerence ( H, OD, ID)

Crushing strength (psi)

±10, ±5, ±10

3600 - 4200

Surface Finish MouldA

25

25

DETAIL A

90

90

DGNFC, PAEC, ISLAMABD

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IndexDate M o d i f i c a t i o n s

21-08-09

RCC BARREL (OUTER DIMENSIONS)

Designed by:

Mian Ahmad Syed, SEChecked by:

M. Aslam Nasir, PEApproved by:

Drawn by:

Mian Ahmad Syed, SE

Unit:

Scale: 1:12.5

WMD-RCC-BB-700WMDWASTE MANGEMENT DIVISION

DGNFC, PAEC, ISLAMABADWMD / CAD /

TITLE

DWG. NO.

Format:

Folio:

REF.

Remarks

10

0

100

1100

900

14

00

Note: All dimensions are in mm

36

U- Channels(MS 125x125x1500)

Angle Iron (37x37x1500)Angle Iron (37x37x1500)

50

MS- RODS (Ø10mm)

525-550

DETAIL C

C

125 125

50

100

MS-PLATE (5x150x150)

MS-PLATE (5x100x150)

50

100

50

100

MS- RODS (Ø10mm)

Note: All dimensions are in mm

PCC 1:2:4

PCC 1:2:4

300 300300 300U- Channels(MS 125x125x1500)

80 80

Designed by:M. Aslam Nasir, PE

Drawn by: Mian Ahmad Syed, SE

OVER PACK FOR 4-MS.DRUMS(200L)

Remarks

REF.

Folio:

Format:

DWG. NO.

TITLE

WMD / CAD /

WASTE MANGEMENT DIVISION

DGNFC, PAEC, ISLAMABAD

WMD WMD-MS-OP-200L

Scale: 1:1

Unit:

Approved by:Checked by:

6-04-10

M o d i f i c a t i o n sDate Index

50

100

MS-Sheet 16 SWG(1.6mm)

MS-Sheet 16 SWG (1.6mm)

80

900-950

Lifting HooksWelded(Ø20 mm)

DETAIL B

B

1200±50

100

1050-1100

1500±100

1500±100

TOP VIEWMS-Sheet 16 SWG(1.6mm)

AA

SECTION AASECTION AA

80

A A

MS-Drum (200L)

MS-Sheet 16 SWG (1.6mm)

TOP VIEW

1500±100

1500±100

80

1050-1100

MS-STRIP FOR REINFORCEMENT (3x50) MS-STRIP FOR REINFORCEMENT (3x50)

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SECTION A-A

FRONT VIEW

(REINFORCEMENT)

15

0

10

0

300

30

0

25

15

0

M.S deformed bars (vertical)

9-13mmØ@ 150mm c/c

M.

S (

Ho

rize

nta

l)

6-1

3m

mØ

@ 2

00

mm

c/c

38

100

AA

TOP VIEWLegs

(REINFORCEMENT)

BOTTOM VIEW

1500

1001300100

15

00

10

0

150

15

0

ANNEXURE-1A

CAP

10

0

25

25

19

13mm@150mm c/c

(b/w)

8-13mmØ@150mm c/c

(b/w)

7-13mm @150mm c/c

15

0

13mm@150mm c/c

30

0

300300

30

0

8-13mmØ@150mm c/c

8-13mmØ@150mm c/c

1260

300

100

300

100

HOOKS ALONG

THE WALL(typ)

CASING FOR EYE BOLT

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ANGLE IRON

1½"X1½"X 316"

3-13mm Ø

300

100

300

100

910

DatedDrawing No. S-1/3

Designed By Drawn by

NR-OP-02-R

RCC Over Pack Container for 4-MS Drums

NR/DGNFCM.Aslam Nasir

Approved by

Manzur Hussain

DCE,DGNR

DG, NR

Tanveer Ahmad (PE)

(WASO)

ANGLE IRON

1½"X1½"X 316"

AT ALL BOTTOM CORNERS(TYPICAL)

ANGLE IRON

1½"X1½"X 316"

B

3-13mm Ø

ANGLE IRON

1½"X1½"X 316"

AT ALL BOTTOM CORNERS(TYPICAL)

DETAIL OF B

ANGLE IRON TO BEWELDED WITH NEAR BYSTEEL BARS (TYPICAL)

Reviewed by

1-3/8" Ø

1-3/8" Ø

6-1

3m

m Ø

@ 2

00

C/C

6-13mm Ø@ 200C/C

140

250

250

200

200

AKHLAQ AHMAD(TECH-1)

13

00

140

10

0

38

(REINFORCEMENT)

TOP CAP VIEW

ANNEXURE-1B

8-13mmØ@150mm c/c

(b/w)

ISOMETRIC VIEWDated

Drawing No. S-2/3

Designed By Drawn by

NR-OP-01-R

RCC Over Pack Container for 4-MS Drums

NR/DGNFCM.Aslam Nasir

Approved by

Manzur Hussain

Principal Engineer

Director, WM

Tanveer Ahmad (PE)

(WASO)

Description Detail

Reinforcement

(all)

13 mm dia

deformed bars

Concrete

Ratio1:1.5:3

Concrete

Strength3700-4000 psi

SPECIFICATIONS

Deformed steel

(ASTM A615

grade 60)

yield strength

60,000 psi

Length of

each wall1500 mm

Height with cap 1260 mm

Wall

thickness100 mm

Outer volume ~3.0 m3

Empty weight

with capping2.84 Tons

Max gross

weight of

filled overpack6.0 Tons (App)

Cap thickness 100 mm

DESIGN TO BE QUALIFIED THROUGH

DROP TEST AS PER APPLICABLE

CODES.

6000 kgs

Reviewed by

MINIMUM OVER LAP OF STEEL BARS = 300mm

AKHLAQ AHMAD(TECH-1)

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Proposed Repository Design Vault Proposed size of Vault - 20x60x7 m Volume of single Vault - 20x60x7 m = 8400 m3

Area of single vault - 20x60 m = 1200 m2

RAW package (5 stacks) in single vault No. of RCC boxes in single vault - 12x36x5 = 2160 No. of RCC Barrels in single vault - 16x48x5 = 3840 Three Vaults can accommodate the annual RAW produced from “C” type reactors

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Module Single module consists of two vaults Volume of single module - 120x20x7 = 16,800 m3 Area of single module - 120x20 = 2,400 m2 RAW package (4 stacks) in a module No. of RCC boxes in single module - 4320 No. of RCC Barrels in single module - 7680

DGNR

Repository Design

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42 DGNR

42

43 DGNR

43

44 DGNR

44

45 DGNR

45

46 DGNR

46

47 DGNR

47

48

Cross section of Capping

system

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Cross section of Capping system continued..

4m

50

Cross section of Capping

system continued..

4m

51

Cross section of Capping

system continued..

4m

52

Cross section of Capping

system continued..

4m

53

Cross section of Capping

system continued..

4m

54

Cross section of Capping

system continued..

4m

55

Cross section of Capping

system continued..

4m

56

Cross section of Capping

system continued..

4m

57

Cross section of Capping

system continued..

4m

5m

58

After Capping

59 59

60 60

Main sources of radioactive waste are; nuclear power, R&D, hospitals, industry etc

Disposal of RAW is in progress

Disposal of LILW is not a big problem

Many countries have developed very good disposal facilities for LLW & ILW

According to national policy, disposal of radioactive waste is responsibility of DGNR,PAEC

DGNR is involved in the development of radioactive waste disposal facilities

The siting process for development of NSDF in progress

Summary

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