letterkenny do009-01

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AnnualEnvironmental

Report

2012 AER

LetterkennyDO009-01

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Table of Contents

Section 1 -Executive Summary and Introduction to 2012 AER………….2Section 2- WWTP Monitoring Report Summary 2012…………………...6Section 3 - Operational Reports Summary…………………………….....20Section 4 -Infrastructural Assessments & Programme Improvements…20Section 5- Environmental Liability and Financial Provisions…………...25Section 6-Lisence specific reports…………………………………….........37Section 7-Certification & sign off statements……………………………..39Section 8-Appendises

Section 1. Executive Summary and Introduction to 2012 AER

1.1 Introduction and background to 2012 AER

The majority of the sewer network is a combined collection system dating from the1950s and 1960s. Several newer areas of residential development are served bypartially separate collection systems. Significant improvements have been carried outon the sewer network since 2004, including the installation of new trunk pipework,three new pumping stations and the decommissioning of two major storm wateroverflows.There are five pumping stations on the sewer network. The main inlet pumping stationis located at Grove Burn, where waste water undergoes preliminary treatment byscreening before being pumped to Letterkenny Waste Water Treatment Plant.Letterkenny Waste Water Treatment plant, located 2.5km east of the town atMagherannan, uses the conventional activated sludge process to reduce the organiccontent of the waste. Waste water is introduced into two aeration tanks, which utilisesurface mechanical aerators. Following aeration the wastewater is conveyed to aclarifier from which the final treated effluent is discharged. As the plant cannot copewith the inflow hydraulic load a bypass system is in operation, hence the final treatedeffluent, combined with the untreated intake bypass flow is discharged directly via anoutfall into the receiving waters of the Lough Swilly Estuary.There is no effluent discharge point within the treatment works itself. Thedischarge from the treatment plant is pumped 1.5km to a point at Thorn Pier inthe upper reaches of the Swilly Estuary. However an emergency overflow existsduring times of outlet pump failure.

Figure 1: Waste Water Treatment Plant Layout

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The Letterkenny Wastewater Discharge Licence was granted on 30th March 2010.This is the second Annual Environmental Report for the Letterkenny WastewaterTreatment Works.

A schematic of the Letterkenny WWTP is shown below. This plant was in use until October 2012when it wasreplace by a new DBO treatment works

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Work commenced on the new Letterkenny Wastewater Treatment Plant and SludgeTreatment Centre in May 2011. Donegal County Council handed over the dailyoperation and maintenance of the wastewater treatment works to the contractorengaged to carry out this Design, Build & Operate contract, Severn Trent

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Water/Response Engineering, in June 2011. The Design & Build contract is scheduledto be complete in March 2013 with the 20 year Operation contract following thereafter.The average population equivalent, PE, for 2012, based on 60g/head/day BOD, iswithin the 22,752 figure included in the EPA’s report ‘Urban Wastewater Dischargesin Ireland for Population Equivalents Greater than 500 Persons, 2006 & 2007’.However, the influent results show that the plant is hydraulically overloaded in thewinter months and biologically overloaded in the summer months with the PEincreasing to 42,346 in early June 2011. The hydraulic overloading in the wintermonths can be attributed to the infiltration of storm water in the combined networkupstream of the treatment plant.

An analysis of the effluent results highlights that the existing treatment plant pre October2012 was notcapable of achieving the Emission Limit Values, ELV, all year round, particularly theBOD, COD, SS and Ammonia parameters. The results reveal that there were ELV for thefirst nine months. However since the influent was put through the “new plan” allsubsequent results have been significantly lower than the Licence requirement.

Monthly sampling of the influent and effluent is carried out by Donegal County CouncilCentralLaboratory Services.

Section 2Letterkenny WWTP Monitoring ReportSummary 2012

2.1 InfluentMonitoring

BOD(mg/l)

COD(mg/l)

SS(mg/l)

OrthoP(mg/l)

Ammonia(as N)

Hydraulicloading m3/d(estimate)

OrganicloadingPE/day)

Number of samples 12 12 12 12 12 12 12Annual Max. 281 3425 1132 2.69 50 17818 66,490Annual Mean 197 560 239 1.77 23.7 6919 22,752

Note: The results for Letterkenny Quality Monitoring Results are included in Appendix 1

An analysis of the influent indicates that the average population equivalent ( p.e.) for2012, based on 60g/head/day BOD, is 22,752

2.2 Summary Report on Discharge from the agglomeration

The primary discharge (SWI) is the outfall from the WWTP to the Swilly Estuary,downstream of the WWTP. The discharge point is located at the Glebe Letterkenny,NGR: 220346E, 41244N.There are no secondary wastewater discharges from the agglomeration.

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It should be noted that as part of the testing and commissioning process of the DBOtreatment plant (under construction) that the old treatment plant was decommissioned andall waste was put through the new plant from September 2012. Subsequently there hasbeen no ELV exceedance in October, November or December 2012.

Discharges from the AgglomerationSummary Table

BOD(mg/l)

COD(mg/l)

SS(mg/l)

Orthophosphate(asP)

Ammonia(as N)

TotalOxidisedNitrogen(mg/l) Comment

WWDL ELV(Schedule A) 25 125 35 2 5 15ELV with condition2 interpretationincludedNumber of Sampleresults 12 12 12 12 12 12Number of Sampleresults aboveWWDL ELV 8 4 7 0 9 3Number of Sampleresults aboveWWDL ELV withCondition 2interpretationincluded 8 4 7 9 3

Annual Mean (forparameters whereELV applies) 44 109 121 8.4 0.9Overall compliance(Pass/Fail

Note: The results for Letterkenny ELVs are shown in Appendix 3

2.3 Treatment Efficiency Report

BOD(kg/day)

COD(kg/day)

SS(kg/day)

Ortho P(kg/day)

Ammonia(as N)kg/day Comment

Influent mass loading(kg/day) average 1192 4611 1528 10.46 144

Effluent mass Emission 329 840 903 3.4 62.9

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2.4: Treatment Capacity Report (new TreatmentNew plant operational from Oct 2012)

Hydraulic Capacity - Design/As Constructed (M3/day) 32,400Hydraulic Capacity - Current loading (m3/day) (avg) 6919Hydraulic Capacity - Remaining (m3/day) 25,481Organic Capacity - Design/ As constructed (PE) 40,000Organic Capacity - Current loading (PE) 22,752Organic Capacity - Remaining (PE) 17,248Will the Capacity be exceeded in the next three years? no

2.5: Ambient Monitoring

Ambient Monitoring Point fromWWDL

Irish GridReference

EPA FeatureCoding Toolcode

Does the Assessment of the ambientmonitoring results indicate that thedischarge is impacting on water quality

downstream location 220388 / 412587 SW2 Nothing observed

upstream location 220354 / 412312 SW1 Nothing observed

Note: The results of the ambient monitoring are included in Appendix 3.

% Efficiency (% reductionof influent load) 72% 81” 41% 67.5% 56%

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The results of the ambient monitoring samples taken, both upstream and downstream, areshown in attached appendix 4.

2.6 Data collection and reporting requirements under the Urban WasteWater Treatment Directive.This information has been submitted electronically by the Donegal County CouncilLaboratory Service under the 2012 EPA Urban Wastewater Returns.

2.7 Pollutant Release and Transfer Register ( PRTR)

Pollution Release

And

Transfer Register

PRTRLetterkenny

2012

11

PRTR

17

PRTR

18

PRTR

19

PRTR

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3.1 Complaints Summary: No complaints received.

3.2 Reported Incidents summary

Location Lab. Ref Date pH Temp BOD COD SSNH3(as

N)NO3(as

N)NO2(as

N) TON Ortho P(mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l)

Emission limit 25 125 35 5 15 2Values(ELV)Letterkenny

combined outlet 122501224 25/01/2012 7.45 35 167 105 9.04 0.835 0.14 0.975 0.314combined outlet 122501540 24/02/2012 7.47 58 102 64 11.7 0.677 0.4 1.077 0.648combined outlet 122501971 30/03/2012 7.37 35 102 61 12.5 0.4 0.401 0.801 0.469combined outlet 122502263 25/04/2012 7.39 113.6 365 216 8.8 0.157 0.274 0.431 0.544combined outlet 122502824 31/05/2012 7.1 20.4 65 30 11.700 <0.100 0.277 0.282 0.465combined outlet 122503347 28/06/2012 7.46 40.3 183 132 14.700 <0.100 0.381 0.217 0.217combined outlet 122503774 20/07/2012 7.46 76.2 62 124 14.200 <0.01 1.69 1.69 0.530combined outlet 122504434 24/08/2012 7.7 73 134 546 11.000 <0.01 0.07 0.075 0.200combined outlet 122504893 28/09/2012 7.12 17.7 68.5 60 143 5.710 <0.100 1.8 1.85 0.43

The above table shows that there were ELVs, (high lighted in red), in each of the monthstested up to September 2012. this is due to the fact that the old treatment works wassignificantly overloaded both hydraulically and organically. However since the newtreatment works was put into operation, all subsequent tests have been within prescribedlimits set out under the discharge licence. The ELVs were not reported to the EPA.

4 Infrastructural Assessments and ProgrammeImprovements

4.0 Treatment Capacity

The old Wastewater Treatment plant, which was in operation until October 2012, wasboth hydraulically and organically overloaded, with consistent ELVs during that period.In October 2012, the New Treatment Plant, while still at construction /process provingstage, was put into operation and all samples tested have consistently being significantlybelow the license discharge limits.The currant organically loading from the agglomeration is estimated at 22,752PE and theDesign capacity of the new treatment works is 40,000PEThe currant hydraulic flow is estimated at 6,919 m3/day and the currant design capacity is32,400m3/day.

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The above figures show that there is significant spare capacity in the new treatment plantand it is unlikely to be overloaded in the foreseeable future.

4.1 Storm Water Overflow Identification and inspection ReportThe New Treatment Plant, which has been designed to be capable of treating effluent toUrban Waste Water Treatment Directive Standards includes for the decommission of theexisting hydraulic by-pass system and has result in a significant improvement with regardto receiving water quality.The DBO contract has also includes the construction of a new storm water holding tank atBallyraine. The storm overflow system, which also came into use in October 2012, allows300 litres/sec to go forward for treatment. Storm flows in excess of this will enter thestorm holding tank which has a capacity of 3,450m3. Wastewater stored in the holdingtank will be pumped to treatment following the storm event. Should the storm continueand the tank fills up, a new discharge to the River Swilly is included. This essentiallymeans that the existing SW11(c), see Schedule A.4, will be discontinued and replacedwith the new discharge location.

A.3 Discharges to be discontinued

ADischargePointCode Note 1

Location Name of ReceivingWaters

Discharge shall ceasefrom

SW2 Hawthorn HeightsDischarges at 216369E, 410914N

Swilly River via stream 31st December 2013

SW3 Oldtown BridgeDischarges at 216677E, 410864N

Swilly River 31st December 2013

SW4 Behind Burnside Apts.Discharges at 216700E, 410885N

Swilly River via DevlinBurn

31st December 2013

SW5 Lower Main St. (Chas Kelly)Discharges at 216700E, 410885N


SW6 Lower Main St. (Voodoo)Discharges at 216700E, 410885N


SW7 Rosemount LaneDischarges at 217342E, 410952N


SW8 Field behind Sprackburn DriveDischarges at 217847E, 410854N

Swilly River viaSprack Burn

31st December 2013

SW9 Access Road to Fire Stn.Discharges at 217847E, 410854N

Swilly River viaSprackburn

31st December 2013

SW11(a) Ballyraine (450mm dia.)Discharges at 218684E, 411239N


SW11(b) Ballyraine (600mm dia.)Discharges at 218639E, 411127N


Note 1: These discharges shall, with the agreement of the Agency, either cease to be upgraded to comply with the definition of a stormwater overflow as set out in “Procedures and Criteria in relation to Storm Water Overflows” published by DoEHLG (1995), by 31st

December 2013.

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WWDL Name/ Code forStorm WaterOverflow

Irish GridReference

Included inScheduleA4 of theWWDL

CompliancewithDoEHLGCriteria

No. of timesactivated in2012(No. ofevents)

Estimated/Measureddata

Total volumedischarged in2012 (m3)

Estimated/Measureddata

???

Yes / No

Yes

Compliant /NotCompliant /Not yetassessed

No. M / E M / E

D0342-01 ??? Yes NotCompliant Not known Not known Not known

D0342-01 219287E,426533N

Yes NotCompliant Not known Not known Not known

4.2 Report on progress made and proposals being developed to meet theimprovement programme requirements

Schedule A.3 above lists the discharges to be discontinued or upgraded to comply withthe definition of a storm water overflow as set out in ‘Procedures and Criteria in relationto Storm Water Overflows’ published by DoEHLG (1995) by 31st December 2013. Interms of progress on this improvement, Donegal County Council can confirm that anupdate of the hydraulic modelling report for the Letterkenny foul sewerage network hasbeen completed. This report has been presented to the Department of Environment,Community & Local Government, DoECLG, as proposed Stage 3 of the LetterkennySewerage Improvement Scheme. Donegal County County Council are awaitingdepartmental approval of the report which proposes improvements within the existingtrunk sewer network, including proposals to discontinue identified storm water overflowsand provision of future extension of the network within the environs of Letterkenny.It is the intention of Donegal County Council to carry out the proposed improvementworks by 31st December 2013, subject to the availability of appropriate funding beingmade available from the DoECLG or Water Ireland.

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SpecifiedImprovementProgrammes(underSchedule Aand C ofWWDL)

LicenceSchedule(A or C)

LicenceCompletionDate

DateExpired?(N/NA/Y)

Status of Works((i) Not Started;(ii) At planningstage; (iii) Workongoing on-site;(iv)CommissioningPhase; (v)Completed; (vi)Delayed;)

%Completed

LicenseeTimeframeforCompletingthe Work

Comments

WWTPupgrade and&improvementworks

Cessation ofhydraulicbypass atWWTP

Installationof new outfalldiffuser atprimarydischargepoint

Installationof stormwater storagetank atBallyraine

UpgradeSWOs

C.1

C.1

C.1

C.1

C.3

31/12/2012

31/12/2012

31/12/2017

31/12/2017

31/12/2013

31/12/2012

31/12/2012

31/12/2012

31/12/2017

NR

Commissioningphase

Commissioningstage

Commissioningstage

Completed

Planning stage

On target

On target

On target

31/12/2012

31/12/2013

Completed

Completed

Completed

completed

Improvement Programme (WWTP) summary table:

Does the Improvement Programme provide anassessment of the existing waste water treatment plantperformance for the following:

Licensee self- assessmentcheck to determine whether allrelevant information isincluded in the Programme ofImprovements

Reference to relevantsection of AER (e.g.Appendix 2 Section 4.

Existing CapacityYes

ELVs Yes

Receiving Water body designation Yes

Downstream abstraction and uses of water Yes

Water quality objectives for the water body Yes

S.16 Water Pollution Act licensed discharges to theworks Yes

Comment

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Sewer Integrity Risk Assessment toolThe network surveying work which is required to make a meaningful return is ongoingand will be submitted as soon as it is completedtable A:

The Improvement Programme shouldinclude an assessment of the integrity of theexisting wastewater works for the following:

Risk AssessmentRating (High,Medium, Low)

Risk Assessment Score

Reference torelevant section ofAER (e.g. Appendix2 Section4.

Hydraulic Risk Assessment Score

Environmental Risk Assessment Score

Structural Risk Assessment Score

Operation & Maintenance RiskAssessment Score

Overall Risk Score for the agglomeration

table B:Are the findings of the Sewer Integrity RiskAssessment included in the ImprovementProgramme?

N.b. each licensee should prioritise the findings of the risk assessment in theImprovement Programme starting with High Risk aspect.

Include a line entry for each improvementidentified

Yes / No % Completed

Reference to relevantsection of theImprovementProgramme.

What % of leakage is reported / estimated? Survey currentlyongoing

%

What % of misconnections is reported /estimated?

Survey currentlyongoing

%

Comment

Improvement Programme (Works) summary tableThe Improvement Programme should include anassessment of the integrity of the existing wastewaterworks for the following:

Licensee self- assessmentcheck to determine whether allrelevant information isincluded in the Programme ofImprovements

Reference to relevantsection of theImprovement Programme.

Capacity of the works Yes

Leaks from the works Yes

What % of leakage is reported? %

Misconnections between foul sewer to surface waterdrainage Survey currently ongoing

What % of misconnections is reported? %

Surface water infiltration Yes / No

Groundwater infiltration Yes / No

Comment

Improvement Programme (Secondary Discharges) summary table:

The Improvement Programme shouldinclude an assessment of SecondaryDischarges (e.g. cease discharge /upgrade tomeet requirements) for the following :

Licensee self- assessmentcheck to determinewhether all relevantinformation is included inthe Programme ofImprovements

Reference to relevantsection of theImprovementProgramme.

Date forcompletion

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Receiving water body designation Yes / No NA

Downstream abstractions and uses ofwater Yes / No

NA

Water quality objectives for the waterbody Yes / No

NA

CommentThere are no secondarywaste water discharges

Preferred format for Improvement Programme (Storm Water Overflows) summarytable:

The findings of the SWO Identification and InspectionReport should be included in the ImprovementProgramme (upgrades to meet licence requirements)

Licensee self- assessment check todetermine whether all relevantinformation is included in theProgramme of Improvements

Reference to relevant sectionof the ImprovementProgramme.

Include a line entry for each SWO improvement Yes / No

Comment

The two existing storm wateroverflows will be improves as partof the capital improvement scheme,currently at Preliminary ReportStage

Improvement Programme (Licence Specific Reports) summary table:The findings of the Licence Specific Reports should beincluded in the Improvement Programme (i.e. anyidentified upgrades to meet licence requirements)

Licensee self- assessment check todetermine whether all relevantinformation is included in theProgramme of Improvements

Reference to relevant sectionof the ImprovementProgramme.

Include a row for each licence specific report finding Yes / No

CommentSee 4.2 above

Improvement Programme (Implementation Plan) summary table:

For each improvement identified theImprovement Programme should include animplementation plan that :

Licensee self- assessment checkto determine whether allrelevant information is includedin the Programme ofImprovements

Reference to relevantsection of the ImprovementProgramme.

Identifies and describe each improvement including atimeframe for implementation? (Cond. 5.3) Yes / No

Specifies the parameters that will be affected by theimprovement? Yes / No

Estimates the costs and source of funding? Yes / No

Estimates the water quality improvement associatedwith the Improvement? Yes / No

Comment

5. Environmental Liability and Financial Provisions

Environmental Liability and Risk Assessment

Donegal County Council

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Environmental Liability Risk Assessment & statement of the Measures forLetterkenny WWTP 2012

Urban waste Water DischargeLicence No. D0342-01

Revision HistoryVersion Status Author Reviewed By

(Grade)Description Date

002 F Howard SEE

Table of Contents

1 Introduction1.1 Background

2 Environmental Sensitivity2.1 Sensitivity of Receiving Waters2.2 Groundwater protection2.3 Protected Ecological sites and Species (shortest distance from any

Discharge)2,4 Human Health

3 Risk prevention/ Mitigation4 Statement of Measures5 Financial provision

1 IntroductionThis environmental Liability risk Assessment relates to the agglomeration of Letterkennyand Environs. This report has been prepared in compliance with condition 7.2 of LicenceD0009-01 which requires the submission of:

An annual statement as to the measures taken or adopted in relation to theprevention of environmental damage,

The financial provisions in place in relation to the underwriting of costs forremedial actions following anticipated events (including closure) oraccidents/incidents, as may be associated with discharges or overflows from thewastewater works.

Environmental Liabilities Risk Assessment (ELRA) to address the liabilities fromthe present or planned discharges, within twelve months of the date of grant ofthis licence

1.1Background :The majority of Letterkenny’s sewer network is a combined collection system datingfrom the 1950s and 1960s. Several newer areas of residential development are served bypartially separate collection systems. Significant improvements have been carried out onthe sewer network since 2004, including the installation of new trunk pipe work, three

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new pumping stations and the decommissioning of two major storm water overflows. Theremaining storm water overflows do not comply with the DoEHLG’s ‘Procedures andCriteria in Relation to Storm Water Overflows’. However work is ongoing in havingthese Storm Water Overflows eliminated in the near future.There are five pumping stations on the sewer network. The main inlet pumping station islocated at Grove Burn, where waste water undergoes preliminary treatment by screeningbefore being pumped to Letterkenny Waste Water Treatment Plant.

Old Plant (decommissioned September 2012)The details of the old plant are set out below, but in October 2012, this plant has beenstood down and replaced with a modern, increased capacity, Design Build Operatefacility.Letterkenny Waste Water Treatment plant, located 2.5km east of the town atMagherannan, uses the conventional activated sludge process to reduce the organiccontent of the waste. Waste water is introduced into two aeration tanks, which utilisesurface mechanical aerators. Following aeration the wastewater is conveyed to a clarifierfrom which the final treated effluent is discharged. As the old plant could not cope withthe inflow hydraulic load, a bypass system was in operation, hence the final treatedeffluent, combined with the untreated intake bypass flow was discharged directly via anoutfall into the receiving waters of the Lough Swilly Estuary.There is no effluent discharge point within the treatment works itself. The discharge fromthe treatment plant is pumped 1.5km to a point at Thorn Pier in the upper reaches of theSwilly Estuary. However an emergency overflow exists during times of outlet pumpfailure.

New Plant, (operational October 2012)The Design Build Operate Contract was officially signed on 18th February, 2011.This contract is currently under construction/commissioning and consists of the following:

New Wastewater Treatment Plant at Maherenan,Sludge Treatment Plant, at BonageeNew storm water holding tank and overflow at BallyrainePipelines and effluent outfall at The Thorn

Wastewater Treatment Processes

The new wastewater treatment plant at Magheranan is built to cater for a loading of40,000 population equivalent. It can take a peak hydraulic load of 375 l/s (3 x DWF +),with storm flows in excess of that being diverted to the storm holding tank at Ballyraineafter screening.Flows to treatment initially pass through a Rotating Bar Interceptor (RBI) Screen wheregross solids larger than 100 mm are removed. The flows are pumped to the inlet Workswhere they undergo fine screening (6mm) followed by grease and grit removal.Biological treatment follows in the form of extended aeration, final settlement andreturned activated sludge. Aeration is achieved through diffused air in twin carouselchambers. De-nitrification is part of the process and there is a facility for Phosphorousremoval during aeration. (Waste activated sludge is treated in another part of the works.)Tertiary treatment is provided with ultra-violet radiation to reduce pathogens before beingdischarged via final effluent pumps into the Swilly estuary tidal zone through diffusers onthe estuary bed.

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In addition to providing this new plant, the contractor, Response Engineering/Severn Trent, isto operate the facility for 20 years under a Design Build Operate Contract.

2.0 Environmental SensitivityQuality of the Swilly EstuaryThe new Wastewater Treatment Plant discharges treated final effluent at the Thorn at alocation within the Swilly Estuary tidal zone categorised by the Environmental ProtectionAgency (EPA) as a “Transitional Waterbody”. This transitional water body spansbetween the Swilly River, roughly upstream of the Oldtown Bridge, Letterkenny, and theCoastal Waterbody, roughly north of a line from Rathmullan to Fahan.

The EPA determines the status of such waterbodies by reference to an extensive range ofparameters, some of which are based on the water quality and others based on aquatic lifein its various forms. Possible resulting Status categories are ‘High’, ‘Good’, ‘Moderate’,‘Poor’ and ‘Bad’. The characterisation of waterbodies was initially carried out throughthe River Basin Management Plans based on data collected between 2008 and 2009. TheOverall Status Result for the Swilly Estuary was “Moderate”. It had scored ‘High’ forsome parameters, ‘Moderate’ for some and ‘Less than Good’ in one case. Data collectedbetween 2010 and up to July 2011 has been reviewed by the EPA and will be published ina Report on Water Quality 2010 – 2012. The date of publication is not yet known, but isexpected shortly. We are advised that the Status Result for the Swilly Estuary will remainas ‘Moderate’ in that report. The data on which that is based pre-dates the commencementof the new WWTW at Letterkenny.

A new round of sampling / testing is ongoing and will be used by the EPA for follow-upreviews of water quality. The earliest date we can expect for an overall review of theStatus of the Swilly Estuary based on data collected since the WWTW has been inoperation will be close to year end 2013. Therefore we are not yet in a position to advisewhat impact the new treatment regime will have on the overall water quality status of theSwilly Estuary. (It should also be noted that the discharges from Letterkenny WWTW arenot the only discharges impacting on the waterbody, though they are significant.)

Notwithstanding the above, the fact that the new WWTW is treating all wastewater fromLetterkenny’s sewers to a high standard compared with the former regime where 30% ormore was by-passing and being discharged untreated must represent a very significantimprovement to the immediate receiving waters.

2.1 Sensitivity of Receiving WatersUsing the EPA Sensitivity Assessment Excel sheet the Sensitivity Rating for thisagglomeration is 2.

2.2 Groundwater ProtectionNo risk determined by Environmental Risk Assessment.

2.3 Protected Ecological Sites and Species (shortest distance from anyDischargeA risk score of 2 has been determined by the Environmental Risk Assessment forProtected Ecological Sites and Species as the discharge location is within or bordering adesignated site.

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2.4 Human HealthNo risk determined by Environmental Risk Assessment.

3.0 Risk Prevention/ Mitigation (old Plant)The Dynamic Risk Enforcement Assessment Methodology (DREAM) uses a decisionmaking framework and toolset to assess the risk posed by the primary discharge from thewaste water agglomeration.

DREAM Risk Assessment (old Plant)

Dream Risk Category Enforcement Category Risk Score

A1 A1 90

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Table 2 Risk Assessment Form (Old Plant)

Letterkenny Table 1 Environmental SensitivityAssessmentEnvironmental Attribute Attribute Score Designated Score Comment Data SourcesSensitivity of Receiving Water EPA MapsClass A (Q5, Q4-5, Q4) 3 Discharge to sea Shellfish AreasClass B (Q3-Q4) 2 2008 Bathing Water MapClass C (Q3, Q2-3) 1Class D (Q2, Q1-2, Q1) 0 0

Designated Costal & EstuarineWaters 2 n/a

Potentially Eutrophic Coastal& Estuarine 1 n/aGroundwater ProtectionRegionally Important Aquifer 2Locally Important Aquifer 1Poor Aquifer 0 0Vulnerability Rating - Extreme 3Vulnerability Rating - High 2

Vulnerability Rating -Moderate 1

Vulnerability Rating - Low 0 0

Protected Ecological Sites and Species (Shortest distance from any discharge)

Discharge within or directlybordering a designated site 2 2<1km 1>1km 0 0Human Health

Discharge within or directlybordering a designatedshellfish area0 - 5 km 1>5 km 0 0

Designated Bathing Water

The appropriate Officershould sign theProgramme ofMeasures

WITHIN 0-5 km 1>5 km 0 0Drinking Water SourceWithin 0-10 km 1>10km 0 0

Environmental Sensitivity Score 2 This value to be stated in your ELRA

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Table 2: Risk Assessment form Letterkenny Old TW Plant

I Risk ID Process* Potential Hazards Environmental effect Severity Rating Basis of Severity Occurrence Rating Basis of Occurrence Risk Score

II

III Electrical Failure Plant shutdownRaw sewage enteringinlet pumping station,overflowing to GroveBurn/ Swilly River

Increase in SS in effluent,High BOD /COD Possibilityof hazardous substancenot metabolised bytreatment works

5 Could havesignificant impacton receiving watersdue to lowassimilativecapacity

2 Power outage 10

IV Large inflow ofstorm waterduring highrainfall. Plantbecomeshydrolicallyoverloaded

High BOD/COD/SSbeing discharged

High BOD & SSIncreased screenings intreatment process

4 Potential forsignificant impacton receiving watersalthough dilutionfactor increased

3 1 in 5 year storm couldoverwhelm plant andbypass system

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V Plant organicallyoverladed

High BOD/COD shockloading. Possibel Haz

substances notmetabolised by plant.

Increased SS.

High Bod, COD,SSdischarge

4 Could havesignificant impacton localwatercoursealthough dilutionfactor increased

3 non compliance withELVs

12

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Table 2: Risk Assessment form Letterkenny New TW Plant

Risk ID Process Potential Hazards EnvironmentalEffect

SafetyRating

Basis of Severity OccurrenceRating

Basis of Occurrence RiskScoreSeverity xoccurrence)

1 Plant hydraulicallyoverloaded duringstorm

Discharge fromstorm overflowtank to Swilly

Untreated(screened)discharge toSwilly

3 Could haveimpact on estuary

2 3500m3 storm wateroverflow tank

6

II Plant organicallyoverloaded

High BOD/CODeffluent

Pollution toestuary


1 Significant SurplusTreatment capacity existsin new plant

5

III Plant shutdown dueto electrical failure

High BOD/CODeffluent

Pollution toestuary


1 Stand by generatorsavailable protocol in placefor testing

5

IV Break down of UVfilter on finaleffluent

Reduceddisinfection-increase in the noof micro orgasmsin effluent

Pollution toestuary


1 Quality of effluent beforeUV treatment is good,protocol in place forregular maintenance of UVequipment

4

V

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Table 3 Risk Matrix Old TW Plant

V. High 5

High 4 VIV

Occ

urre

nce

Medium 3

Low 2

III

V. Low 1

Trivial Minor Moderate Major Massive

1 2 3 4 5Severity

Table 3 Risk Matrix New TW Plant

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V. High 5

High 4

Occ

urre

nce

Medium 3

I

Low 2

V. Low 1IV

IIIII

Trivial Minor Moderate Major Massive

1 2 3 4 5Severity

Table 6 Risk Classification - Occurrence

The appropriate Officer should sign the Programme of MeasuresRating Occurrence

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Category Description Likelihood ofOccurrence (%)

1 Very LowVery low chance (0-5%) ofhazard occurring in 30 yrperiod *

0 – 5

2 LowLow chance (5-10%) ofhazard occurring in 30 yrperiod

5 - 10

3 MediumMedium chance (10-20%)of hazard occurring in 30 yrperiod

10 - 20

4 HighHigh chance (20-50%) ofhazard occurring in 30 yrperiod

20 - 50

5 Very HighGreater than 50% chanceof hazard occurring in 30 yrperiod

>50

Table 5Risk classification Table - Severity

Rating Severity

Category Description Cost of Remediation

1 TrivialNo damage or negligiblechange to the environment. €1,000

2 MinorMinor impact/localised ornuisance €5,000

3 ModerateModerate damage toenvironment €10,000

4 MajorSevere damage to localenvironment €100,000

5 MassiveMassive damage to a largearea, irreversible in mediumterm

€1,000,000

2 Statement of Measures

The measures to be taken by Donegal County Council are outlined below.

With the commissioning of a new treatment works with a PE of 40,000 , hydraulic capacity of32,400 m3 and the construction of a storm water overflow tank at the Ballyraine, risks 1, 4, and5 have been eliminated or significantly reduced during the year 2012.

36

Table 4 Statement of Measures

RiskID

RiskScore

MitigationMeasuresto be taken

Outcome Action Date forcompletion

ContactPerson

I 10 Regularmaintenanceof pumps atinlet pumpingstation

High leveloverflow doesnot come intooperation

Dailymonitoring byDBOoperationalstaff

October 2012 FHowardSEE

2 8 Regularmaintenanceof pumps atoutletpumpingstation

High leveloverflow doesnot come intooperation

Dailymonitoring byDBOoperationalstaff

October2012

FHowardSEE

3 10 RegularInspectionof electricalandmechanicalplant

Continuouspower supply

Acquisitionof standby 3phasegenerator

October2012

FHowardSEE

4 12 Assessmentofstormwaterinflow tonetwork

Reducedinfiltration ofstormwater

Increasestormwateroverflowtank

October2012

FHowardSEE

5 12 Upgrade ofplant andequipment

Modernisationof Plant andIncreasecapacity

CapitalworksUnderconstruction

2012 Mr PaulKilcoyneSEE

In May 2011, work commenced on the new Letterkenny Wastewater Treatment Plant and SludgeTreatment Centre in May 2011. This Design, Build & Operate contract, being carried out bySevern Trent Water/Response Engineering Ltd. is scheduled to be complete in March 2013 withthe 20 year Operation contract following thereafter.

However the new plant, while still in the construction phase, was put into operation in October2012.All subsequent samples tested have been significantly lower than the permitted ELV.The DBO contract provides for an upgraded 40,000 p.e. secondary treatment plant which will becapable of treating effluent to Urban Waste Water Treatment Directive Standards. This willdecommission the existing hydraulic by-pass system and result in a significant improvement withregard to receiving water quality. The DBO contract also includes the construction of a newstorm water holding tank at Ballyraine. The storm overflow system will allow 300 litres/sec to go

37

forward for treatment. Storm flows in excess of this will enter the storm holding tank which has acapacity of 3,450m3. Wastewater stored in the holding tank will be pumped to treatmentfollowing the storm event. Should the storm continue and the tank full up, a new discharge to theRiver Swilly is included. This essentially means that the existing SW11(c), see Schedule A.4,will be discontinued and replaced with the new discharge location. The discharge location (Gridreference 6N, 6E) shall be notified to the EPA prior to activation of the storm water overflow.Donegal County Council can confirm that an update of the hydraulic modelling report for theLetterkenny foul sewerage network has been completed. This report has been presented to theDepartment of Environment, Community & Local Government, DoECLG, as proposed Stage 3of the Letterkenny Sewerage Improvement Scheme.

Donegal County County Council are awaiting departmental approval of the report whichproposes improvements within the existing trunk sewer network, including proposals todiscontinue identified storm water overflows and provision of future extension of the networkwithin the environs of Letterkenny. The infrastructural improvements outlined in Schedule A.3specified Improvement Programme can only be implemented subject to appropriate fundingbeing made available from the DoECLG or a similar governmental funding source.

3 Financial Provisions

Condition 7.22 of the discharge Licence requires the Council to procure an independentconsultant to provide a comprehensive and fully costed Environmental Liability Risk Assessmentto address the liabilities from present and planned discharges. The report was to form part of thesecond AER. This report has been delayed, awaiting the final commissioning of the new WWTPplant expected in 2013.

The infrastructural improvements specified in Schedule A.3 (discharges to be discontinued) willbe completed subject to funding being made available from the DoECLG or a similargovernmental funding source.It is the intention of Donegal County Council to carry out the proposed improvement works byDecember 2013, subject to the availability of appropriate funding.

6 Licence Specific Reports Not relevant

Mitigation Measures

Donegal County Council has a monitoring regime in place, which is aligned with the conditionsin the Licence granted for the discharge(s). This regime will identify any problems which mayoccur with the discharge(s) and if required appropriate action will be taken. Donegal CountyCouncil will make every effort to implement any improvement works required by the licencesubject to available funding.

Management of Financial Risk

38

Currently Donegal County Council has no insurance policy set up to cover for environmentalliability as a result of an accident/incident at a wastewater treatment plant. Donegal CountyCouncil has contacted their insurers, Irish Public Bodies Mutual Insurance Limited (IPB) on thismatter.

Signed Director of ServiceJoe Peoples

Date 26/09/2013

39

7 Certification and Sign Off

7.1 Declaration by director of Services

. Licence Modification Status

There is no need for a modification to the Licence at this time.

. Technical amendment Status

There is no need for a technical amendment to the Licence at this time.

. Licence Review status

There is no need for a Licence Review at this time.

Declaration by Director of Services

This AER includes:

. An executive summary

. An assessment of the performance of the Waste Water Works

. Environmental Liability and Financial Provisions

. Any outstanding reports and assessments have been included as an appendixto this AER.

I certify that the information given in this Annual Environmental Report is truthful,accurate and complete

Signed by

Date*Print signature Name Joe Peoples

Position in Organisation Director of Services

39

40

Appendix 1 Quality results

Location Lab. Ref Date pH COND BOD COD SS NH3(as N) NO3(as N) NO2(as N) TON Ortho P Total N Total P FLOW

(mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) m3/day

January

Letterkenny - inlet 122501222 25/01/2012 7.39 506 140 327 133 13.3 0.159 0.099 0.988 3.18 5881

Letterkenny - combined 122501224 25/01/2012 7.45 497 35 167 105 9.04 0.835 0.14 0.314 12.4 1.33 10408

Letterkenny - outlet 122501223 25/01/2012 7.43 493 9.1 32 31 3.23 1.72 0.221 0.063 0.391 10408

Feburary

Letterkenny - inlet 122501538 24/02/2012 7.38 543 58 183 121 14.1 0.278 <0.01 1.2 2.3 5901


Letterkenny - outlet 122501539 24/02/2012 7.58 544 4 47 11 5.59 2.48 0.123 0.069 0.32 10677

March

Letterkenny - inlet 122501969 30/03/2012 6.96 753 126.1 557 292 40 <0.100 <0.01 4 6.12 4566



April

Letterkenny - inlet 122502261 25/04/2012 7.37 665 177.6 321 212 27.1 <0.100 <0.01 2.2 4.25 4458

Letterkenny - combined 122502263 25/04/2012 7.39 577 113.6 365 216 8.8 0.157 0.274 0.544 30.9 3.13 5972


May

Letterkenny - inlet 122502822 31/05/2012 7.21 655 164.8 397 88 33.600 <0.100 <0.01 <0.100 2.690 4.24 4388

Letterkenny - combined 122502824 31/05/2012 7.1 619 20.4 65 30 11.700 <0.100 0.277 0.282 0.465 20.4 1.07 5862

Letterkenny - outlet 122502823 31/05/2012 7.03 452 35.6 131 123 1.180 0.865 0.235 1.1 0.086 1.17 5862

Letterkenny - outlet 122502351 04/05/2012 7.44 659 122 367 102 20.6 <0.100 <0.01 1.5 3.34 4408

June

Letterkenny - inlet 122503345 28/06/2012 7.2 517 281 318 145 14.200 <0.100 <0.01 <0.100 0.807 21.7 3.18 4935


Letterkenny - outlet 122503346 28/06/2012 7.85 628 3.18 74 27 6.300 0.808 0.262 1.07 0.059 16.2 0.688 7556

July

Letterkenny - inlet 122503772 20/07/2012 7.39 620 131.6 206 48 24.000 <0.100 <0.01 <0.100 2.330 32.2 3.68 4715



41

August

Letterkenny - inlet 122504432 24/08/2012 7.22 1554 814 3425 1132 50.000 <0.100 0.8 0.85 2.000 104.9 15.7 4901

Letterkenny - combined 122504434 24/08/2012 7.7 559 73 134 546 11.000 <0.01 0.07 0.075 0.200 14.9 3.8 7448


September

Letterkenny - inlet 122504891 28/09/2012 7.02 641 106.7 173 77 20.900 0.02 <0.01 0.025 2.11 37.400 4331



October(New scheme)

Letterkenny - inlet 122505322 31/10/2012 7.44 445 111 146 148 12.900 <0.100 <0.01 <0.100 1.01 18.400 2.180 17818

Letterkenny - outlet 122505323 31/10/2012 7.42 443 2.36 25 8 0.650 1.66 <0.01 1.665 0.548 16.800 0.674 18105

November(New Scheme)

Letterkenny - inlet 122505815 29/11/2012 7.24 575 86.4 155 125 17.700 <0.100 <0.01 <0.100 1.43 14.400 2.240 11733


December(New Scheme)

Letterkenny - inlet 122506096 13/12/2012 7.51 707 170.4 512 346 17.000 <0.100 0.188 0.238 0.428 42.300 4.860 9402

Letterkenny - outlet 122506097 13/12/2012 7.59 518 5.29 17 10.5 0.305 <0.100 <0.01 0.055 0.035 1.400 0.220 9119

Appendix 2

Schedule B1 licence

Location Lab. Ref Date pH T COND BOD COD SS NH3(as N) NO3(as N) NO2(as N) TON Ortho P Total N Total P

Metal andorganic

compounds ToxicityVisual

Inspection OFG FLOW(mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) M3/day

Letterkenny Monthly Monthly Monthly Monthly Monthly Monthly Monthly Monthly Monthly Monthly Monthly As Required As Required Daily Quartly Continuouscombined outlet 122501224 25/01/2012 7.45 497 35 167 105 9.04 0.835 0.14 0.975 0.314 12.4 1.33 Not Tested Not tested Cloudy 10 360combined outlet 122501540 24/02/2012 7.47 581 58 102 64 11.7 0.677 0.4 1.077 0.648 16.3 1.96 Not Tested Not tested Cloudy 8 12 063combined outlet 122501971 30/03/2012 7.37 643 35 102 61 12.5 0.4 0.401 0.801 0.469 18.9 1.41 Not Tested Not tested Cloudy 4.7 5378combined outlet 122502263 25/04/2012 7.39 577 113.6 365 216 8.8 0.157 0.274 0.431 0.544 30.9 3.13 Not Tested Not tested Cloudy 16 7039combined outlet 122502824 31/05/2012 7.1 619 20.4 65 30 11.700 <0.100 0.277 0.282 0.465 20.4 1.07 Not Tested Not tested Cloudy 5883combined outlet 122503347 28/06/2012 7.46 580 40.3 183 132 14.700 <0.100 0.381 0.217 0.217 16.1 1.64 Not Tested Not tested Cloudy 5.5 7556combined outlet 122503774 20/07/2012 7.46 610 76.2 62 124 14.200 <0.01 1.69 1.69 0.530 18.9 2.39 Not Tested Not tested Cloudy 4.66 6611combined outlet 122504434 24/08/2012 7.7 559 73 134 546 11.000 <0.01 0.07 0.075 0.200 14.9 3.8 Not Tested Not tested Cloudy 7448combined outlet 122504893 28/09/2012 7.12 17.7 508 68.5 60 143 5.710 <0.100 1.8 1.85 0.43 13.600 2.310 Not Tested Not tested Cloudy 14.6 7481

New Scheme

New outlet 122505323 31/10/2012 7.42 11 443 2.36 25 8 0.650 1.66 <0.01 1.665 0.548 16.800 0.674 Not Tested Not tested Clear <1 18105New outlet 122505816 29/11/2012 7.7 478 2.32 28 8 0.591 1.23 0.486 1.716 0.144 7.900 0.32 Not Tested Not tested Clear 11363New outlet 122506097 13/12/2012 7.59 518 5.29 17 10.5 0.305 <0.100 <0.01 0.055 0.035 1.400 0.220 Not Tested Not tested Clear 9119

Appendix 3Schedule A1 compliance

42

Location Lab. Ref Date pH Temp BOD COD SSNH3(as

N)NO3(as

N)NO2(as

N) TON Ortho P(mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) (mg/l)

Emissionlimit 25 125 35 5 15 1

Values(ELV)Letterkenny

combinedoutlet 122501224 25/01/2012 7.45 35 167 105 9.04 0.835 0.14 0.975 0.314

combinedoutlet 122501540 24/02/2012 7.47 58 102 64 11.7 0.677 0.4 1.077 0.648

combinedoutlet 122501971 30/03/2012 7.37 35 102 61 12.5 0.4 0.401 0.801 0.469

combinedoutlet 122502263 25/04/2012 7.39 113.6 365 216 8.8 0.157 0.274 0.431 0.544

combinedoutlet 122502824 31/05/2012 7.1 20.4 65 30 11.700 <0.100 0.277 0.282 0.465

combinedoutlet 122503347 28/06/2012 7.46 40.3 183 132 14.700 <0.100 0.381 0.217 0.217

combinedoutlet 122503774 20/07/2012 7.46 76.2 62 124 14.200 <0.01 1.69 1.69 0.530

combinedoutlet 122504434 24/08/2012 7.7 73 134 546 11.000 <0.01 0.07 0.075 0.200

combinedoutlet 122504893 28/09/2012 7.12 17.7 68.5 60 143 5.710 <0.100 1.8 1.85 0.43

New SchemeNew outlet 122505323 31/10/2012 7.42 11 2.36 25 8 0.650 1.66 <0.01 1.665 0.548New outlet 122505816 29/11/2012 7.7 2.32 28 8 0.591 1.23 0.486 1.716 0.144New outlet 122506097 13/12/2012 7.59 5.29 17 10.5 0.305 <0.100 <0.01 0.055 0.035

43

Appendix 4 Ambient monitoring

Appendix 5 PRTR outletNAME of WWTP:Letterkenny

Location/Month Lab Ref Date pH Cond. BOD COD SS NH3 as NNitrate(as N)

Nitrite(as N) Ortho P Total N Total P Flow

DailyMassFlowBOD

Daily Mass FlowCOD

Daily MassFlow SS

DailyMassFlowNH3

DailyMassFlowNO3

DailyMassFlowNO2

DailyMassFlow

Ortho P

DailyMassFlow

Total N

DailyMassFlow

Total P

AnnualMassFlow

Ms/cm (mg/l) (mg/l) (mg/l) Mg/l (mg/l) (mg/l) (mg/l) (mg/l) (mg/l) kgs/Day kgs/Day kgs/Day kgs/Day kgs/Day kgs/Day kgs/Day kgs/Day kgs/DayCubicMtrs

JanuaryInlet 1.23E+08 25/01/2012 7.39 506 140 327 133 13.3 0.159 0.099 0.988 3.18

Combined Outlet 1.23E+08 25/01/2012 7.45 497 35 167 105 9.04 0.835 0.14 0.314 12.4 1.33 10408 364.28 1738.136 1092.84 94.08832 8.69068 1.45712 3.268112 129.0592 13.84264Treated Outlet 1.23E+08 25/01/2012 7.43 493 9.1 32 31 3.23 1.72 0.221 0.063 0.391

FebruaryInlet 1.23E+08 24/02/2012 7.38 543 58 183 121 14.1 0.278 <0.01 1.2 2.3

Combined Outlet 1.23E+08 24/02/2012 7.47 581 58 102 64 11.7 0.677 0.4 0.648 16.3 1.96 10677 619.266 1089.054 683.328 124.9209 7.228329 4.2708 6.918696 174.0351 20.92692Treated Outlet 1.23E+08 24/02/2012 7.58 544 4 47 11 5.59 2.48 0.123 0.069 0.32

MarchInlet 1.23E+08 30/03/2012 6.96 753 126.1 557 292 40 <0.100 <0.01 4 6.12

Combined Outlet 1.23E+08 30/03/2012 7.37 643 35 102 61 12.5 0.4 0.401 0.469 18.9 1.41 5110 178.85 521.22 311.71 63.875 2.044 2.04911 2.39659 96.579 7.2051

Location Lab. Ref Date pH DO BODAmmonia

(as N) DINOrtho

PTotal

N ChlorophyllVisual

Inspection

Metal andOrganicCompounds

(mg/l) (mg/l) (mg/l) (mg/l) (mg/l)

4/yr 4/yr 4/yr 4/yr 4/yr 4/yr 4/yr 4/yr 4/yr As Required

D/S SW 1-point 1 122505413 05/11/2012 7.55 10.5 1.71 0.161 0.581 0.113 2.21 3.79 Nothing Observed NTD/S SW 1-point 1 122505574 19/11/2012 8.22 11.2 3.26 0.578 0.881 0.097 2.54 10.27 Nothing Observed NTD/S SW 1-point 2 122505575 19/11/2012 8.01 11.2 3.08 0.303 0.635 0.1 9.99 8.66 Nothing Observed NTD/S SW 1-point 1 122506042 11/12/2012 8.05 13.3 2.43 0.174 0.568 0.019 1.44 5.73 Nothing Observed NTD/S SW 1-point 2 122506043 11/12/2012 8.17 11.9 2.87 0.112 0.37 0.018 0.93 4.91 Nothing Observed NTD/S SW 1-point 1 122506132 13/12/2012 7.5 11.9 2.64 0.227 0.661 0.079 1.57 9.49 Nothing Observed NTD/S SW 1-point 2 122506133 13/12/2012 7.53 11.8 2.58 0.153 0.443 0.084 1.19 5.89 Nothing Observed NT

Nothing Observed NTU/S SW1 122505412 05/11/2012 7.79 11 1.26 0.028 0.418 0.029 1.06 3.79 Nothing Observed NTU/S SW1 122505573 19/11/2012 8 11 3.08 0.239 0.472 0.077 2.15 8.85 Nothing Observed NTU/S SW1 122506041 11/12/2012 7.97 12.1 1.76 0.119 0.412 0.016 1.05 5.5 Nothing Observed NTU/S SW1 122506131 13/12/2012 7.88 12 2.53 0.174 0.543 0.063 1.42 8.27 Nothing Observed NT

44

Treated Outlet 1.23E+08 30/03/2012 7.34 636 8.56 58 16 16.7 3.039 0.971 0.335 0.757

AprilInlet 1.23E+08 25/04/2012 7.37 665 177.6 321 212 27.1 <0.100 <0.01 2.2 4.25

Combined Outlet 1.23E+08 25/04/2012 7.39 577 113.6 365 216 8.8 0.157 0.274 0.544 30.9 3.13 5972 678.4192 2179.78 1289.952 52.5536 0.937604 1.636328 3.248768 184.5348 18.69236Treated Outlet 1.23E+08 25/04/2012 7.3 531 7.72 45 13 3.6 4.637 0.583 0.049 0.28

MayInlet 1.23E+08 31/05/2012 7.21 655 164.8 397 88 33.600 <0.100 <0.01 2.690 4.24

Combined Outlet 1.23E+08 31/05/2012 7.1 619 20.4 65 30 11.700 0.1 0.277 0.465 20.4 1.07 5862 119.5848 381.03 175.86 68.5854 0.5862 1.623774 2.72583 119.5848 6.27234Treated Outlet 1.23E+08 31/05/2012 7.03 452 35.6 131 123 1.180 0.865 0.235 0.086 1.17

JuneInlet 1.23E+08 28/06/2012 7.2 517 281 318 145 14.200 <0.100 <0.01 0.807 21.7 3.18

Combined Outlet 12253347 28/06/2012 7.46 580 40.3 183 132 14.700 0.1 0.381 0.217 16.1 1.64 7556 304.5068 1382.748 997.392 111.0732 0.7556 2.878836 1.639652 121.6516 12.39184Treated Outlet 1.23E+08 28/06/2012 7.85 628 3.18 74 27 6.300 0.808 0.262 0.059 16.2 0.688

JulyInlet 1.23E+08 20/07/2012 7.39 620 131.6 206 48 24.000 <0.100 <0.01 2.330 32.2 3.68

Combined Outlet 1.23E+08 20/07/2012 7.46 610 76.2 62 124 14.200 0.01 1.69 0.530 18.9 2.39 6611 503.7582 409.882 819.764 93.8762 0.06611 11.17259 3.50383 124.9479 15.80029Treated Outlet 1.23E+08 20/07/2012 7.47 610 11.2 50 6 8.340 2.24 2.16 0.030 15.2 0.262

AugustInlet 1.23E+08 24/08/2012 7.22 1554 814 3425 1132 50.000 <0.100 0.8 2.000 104.9 15.7

Combined outlet 1.23E+08 24/08/2012 7.7 559 73 134 546 11.000 0.01 0.07 0.200 14.9 3.8 7448 543.704 998.032 4066.608 81.928 0.07448 0.52136 1.4896 110.9752 28.3024Treated Outlet 1.23E+08 24/08/2012 7.87 575 7.68 36 51 7.900 1.12 2.72 0.030 12.4 0.844

SeptemberInlet 1.23E+08 28/09/2012 7.02 641 106.7 173 77 20.900 0.02 <0.01 2.11 37.400

Combined outlet 1.23E+08 28/09/2012 7.12 508 68.5 60 143 5.710 0.1 1.8 0.43 13.600 2.310 7481 512.4485 448.86 1069.783 42.71651 0.7481 13.4658 3.21683 101.7416 17.28111Treated Outlet 1.23E+08 28/09/2012 7.21 495 3.98 41 17 0.510 2.37 1.74 0.03 9.700 0.484

OctoberInlet 1.23E+08 31/10/2012 7.44 445 111 146 148 12.900 <0.100 <0.01 1.01 18.400 2.180

Final Outlet 1.23E+08 31/10/2012 7.42 443 2.36 25 8 0.650 1.66 0.01 0.548 16.800 0.674 18105 42.7278 452.625 144.84 11.76825 30.0543 0.18105 9.92154 304.164 12.20277

NovemberInlet 1.23E+08 29/11/2012 7.24 575 86.4 155 125 17.700 <0.100 <0.01 1.43 14.400 2.240

Final Outlet 1.23E+08 29/11/2012 7.7 478 2.32 28 8 0.591 1.23 0.486 0.144 7.900 0.320 11363 26.36216 318.164 90.904 6.715533 13.97649 5.522418 1.636272 89.7677 3.63616

DecemberInlet 1.23E+08 13/12/2012 7.51 707 170.4 512 346 17.000 <0.100 0.188 0.428 42.300 4.860

Final Outlet 1.23E+08 13/12/2012 7.59 518 5.29 17 10.5 0.305 0.1 0.01 0.035 1.400 0.220 9119 48.23951 155.023 95.7495 2.781295 0.9119 0.09119 0.319165 12.7666 2.00618

TOTAL 105712 3942.147 10074.55 10838.73 754.8822 66.07379 44.87038 40.28489 1569.808 158.5601328.5122 839.5462 903.2275 62.90685 3.357074

STEP2 0.037291 0.095302 0.102531 0.007141 0.000625 0.000424 0.000381 0.01485 0.0015

STEP 103808.9 265294 285417.1 19878.37 1739.926 1181.575 1060.825 41337.86 4175.375 2783722

45

3

Estimate 21685.49 1898.101 1288.991 1157.264 45095.85 4554.955

Appendix 6 P.E. calculation

Location Lab. Ref. Date BOD Flow BOD Kg/Day P.E.Mg/l m3

Letterkenny - inlet 122501222 25/01/2012 140 5881 823 13722Letterkenny - inlet 122501538 24/02/2012 58 5901 342 5704Letterkenny - inlet 122501969 30/03/2012 126.1 4566 576 9596Letterkenny - inlet 122502261 25/04/2012 177.6 4458 792 13196Letterkenny - inlet 122502822 31/05/2012 164.8 4388 723 12052Letterkenny - inlet 122503345 28/06/2012 281 4935 1386 23112Letterkenny - inlet 122503772 20/07/2012 131.6 4715 620 10341Letterkenny - inlet 122504432 24/08/2012 814 4901 3939 66490Letterkenny - inlet 122504891 28/09/2012 106.7 4331 462 7702Letterkenny - inlet 122505322 31/10/2012 111 17818 1978 32963Letterkenny - inlet 122505815 29/11/2012 86.4 11733 1014 16895Letterkenny - inlet 122506096 13/12/2012 170.4 9402 1602 26701

AV19,872

after omitred

AV15,635

New Scheme

Letterkenny - inlet 122505322 31/10/2012 111 17818 1978 32963Letterkenny - inlet 122505815 29/11/2012 86.4 11733 1014 16895Letterkenny - inlet 122506096 13/12/2012 170.4 9402 1602 26701

46

Av25,520

Design PE 40,000

Appendix 7 UV results

Location Lab. Ref. Date Total Faecal UV Transmission UV Absorption CommentsColiforms coliforms 1cm cell - %

Per 100mlsPER

100MLSLetterkenny outlet(New)

Outlet - before UV 122505324 31/10/2012 58,100 9,700122505817 29/11/2012 106,000 25,000122506098 13/12/2012 131,700 46,500

Outlet - After UV 122505325 31/10/2012 5,794 512 60.6 0.218122505818 29/11/2012 178 91122506099 13/12/2012 >2419.6 2419.6 51.3

47

Appendix 8 Emergency Response Procedure/Corrective Action

59

Appendix 8 Maintenance Procedure

The Maintenance Procedures are contained within the PublicAwareness & Communications file and are available forinspection at the offices of Donegal County Council’s, Water &Environment Services Department, Letterkenny Public ServicesCentre, Neil T Blaney Road, Letterkenny, County Donegal

Appendix 9 Public Awareness & communications Programme

Donegal County Council has put in place a Public Awareness& Communications Programme file in relation to theletterkenny Treatment Plan. This file is held in the LetterkennyPublic Services Centre and can be viewed at Letterkenny PublicServices centre, Neilt T Blaney Road, Letterkenny, CountyDonegal.

letterkenny do009-01

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