Nenagh AER 2009 - tipperarycoco.ie · Section 7.1. Nenagh STP Upstream Test Results 2009. StationName SampleLabCode SampleDate Ammonia as (N) Ammonium (NH4) BOD Chemical Oxygen Demand

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Annual Environmental Report 2009 Nenagh Agglomeration Nenagh Agglomeration was issued with a Waste Water Discharge Licence on 25/9/08. Licence Register Number D0027-01. This is the Annual Environmental Report (AER) for 2009 as required under Condition 6.10 of said Licence. It contains the information required under Schedule D of the Licence.

1. Discharges from the agglomeration Nenagh Agglomeration uses the same primary discharge point, emergency overflows and stormwater overflows as identified in the Waste Water Discharge Authorisation Licence Application. The secondary discharge point was not in use in 2009. There have been no changes to these discharge points since the application was lodged in December 2007. The primary discharge point was sampled 20 times in 2009 (all composite samples). The monitoring test results of the primary discharge satisfied the criteria set out under the Urban Waste Water Treatment Regulations. All samples taken of the primary discharge since the WWDL was issued were within the Emission Limit Values (ELV) for Nenagh as set out in Schedule A of the Licence.

Please find attached an Excel Spreadsheet called “Nenagh STP Final Effluent Test Results 2009”. This spreadsheet shows all sample test results for Nenagh WWTP Final effluent in 2009.

2. Summary report on (i) monthly influent monitoring and (ii) loading removal

efficiencies

2.(i) In 2009, 20 composite influent samples were taken at Nenagh WWTP, at monthly intervals. Please find attached an Excel Spreadsheet called “Nenagh STP Plant Influent Test Results 2009” (This spreadsheet shows all sample test results for Nenagh WWTP Influent in 2009.)

2(ii) Composite Final Effluent samples were also taken on the same days as the Plant Influent samples. By comparing the percentage reduction of the relevant parameters in the effluent samples, the loading removal efficiencies were estimated. Please find attached an Excel Spreadsheet called “Summary report on loading removal efficiencies Nenagh 2009” (which gives a breakdown for all the parameters mentioned in Schedule A:A.1).

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The average BOD removal rate was 97.16%. The range varied from 86.67% to 99.40%. The average Ammonia removal rate was 97.3%. The range varied from 87.89% to 99.86%. The average COD removal rate was 94.2%. The range varied from 73.33% to 99.0%. The average Suspended solids removal rate was 95.72%. The range varied from 71.25% to 99.73%. The average Total Phosphorus removal rate was 88.19%. The range varied from 64.75% to 95.52%. The average Total Nitrogen removal rate was 60.07%. The range varied from 34.67% to 87.1%.

3. Data collection and reporting requirements under the Urban Waste Water

Treatment Directive Nenagh Agglomeration’s WWTP is included in North Tipperary County Council’s 2009 Annual Waste Water Returns Report to the EPA. This report was lodged by North Tipperary County Council with the EPA by 26 February 2010.

4. Complaints summary

There have been no environmental complaints about Nenagh Agglomeration in 2009. The only concerns from the public relating to the agglomeration relate to blocked sewer mains in various areas of Nenagh Agglomeration. These are dealt with by North Tipperary County Council swiftly (usually within 24 hours). The number of blocked mains varies, but the average figure is approximately 2 blockages per week.

5. Pollutant Release and Transfer register- report for previous year

A Pollutant Release and Transfer Register (Condition 4.14) has been completed for Nenagh Agglomeration for the year 2009. This report has been submitted electronically and is included in this AER.

6. Pollutant Release and Transfer register- report for current year There is no expected change from the 2009 PRTR for 2010.

7. Ambient monitoring summary In 2009, ambient sampling consisted of 12 samples taken (i) upstream and (ii) downstream of the primary discharge point. Please find attached 2 No. Excel Spreadsheets called “Nenagh STP Upstream Test Results 2009” and “Nenagh STP Downstream Test Results 2009” attached. These spreadsheets show all test result values for samples taken upstream and downstream of Nenagh WWTP’s Primary Discharge Point in 2009.

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8. Storm water overflow inspection and assessment report

No Storm water overflow inspection and assessment report has been completed in 2009. It is expected to be completed in 2010. North Tipperary County Council visually inspects these overflows, twice weekly, and has found that these stormwater overflows only perform in stormwater conditions.

9. Storm Water Overflow assessment of compliance (every 3 years) No Storm Water Overflow assessment of compliance has been completed in 2009. It is expected to be completed in 2010.

10. Reported incidents summary

There were no reported incidents in 2009.

11. Report on progress made and proposals being developed to meet the

improvement programme requirements. The Draft Preliminary Report and Environmental Impact Statement for the upgrade of Nenagh Waste Water Treatment Plant and its sewer network was completed in the last quarter of 2009. This report proposes to assess and identify deficiencies in the waste water treatment plant, existing sewage and storm collection network and to recommend upgrading works where required. This project will cater for the development of Nenagh agglomeration for the next 20 years. This project proposes to assess and identify deficiencies in the existing sewerage and storm water collection network and to upgrade the network to cater for the development of Nenagh Agglomeration over the next 50 years. The report will 1. Recommend a phased approach to the collection system and treatment plant

construction, as necessary to meet the short term, intermediate and ultimate design life of 50 years.

2. Provide for separate foul and storm sewers, upgrading deficient sewers and built new sewers as required.

3. Submit proposals for minimizing storm flows and dealing with any infiltration to the existing foul system.

4. Review existing pumping stations and identify the need for future pumping stations.

5. Conduct flow and load surveys on the existing network. 6. Conduct CCTV surveys on the existing network. 7. Make recommendations on the upgrade of the SCADA/telemetry systems for

the collection system. It is expected this preliminary report will identify sewer sections that are currently at capacity. These will be replaced with sewers with increased capacity. Older,

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damaged sewers will be replaced to prevent groundwater infiltration and storm water overflows will be assessed and eliminated if possible.

12. Development/Infrastructural works summary (completed in previous year or prepared for current year) In 2009, no major wastewater infrastructure was undertaken. In 2010, no major wastewater infrastructure is expected to be undertaken.

13. Statement of measures required to prevent environmental damage under

Environmental Liabilities Directive (2004/35/EC) It is the goal of North Tipperary County Council to prevent environmental damage under Environmental Liabilities Directive (2004/35/EC). North Tipperary County Council has completed an Environmental Liabilities Risk Assessment to address the liabilities from present or planned discharges. North Tipperary County Council is currently in negotiation with an insurance company in order to put in place financial provisions in relation to the underwriting of costs for remedial actions following anticipated events or accidents/incidents, as may be associated with discharges or overflows from the waste water works. The details of the financial provision/insurance will be submitted to the Agency as soon as they are completed.

14. Assessment of predicted impact on habitats

It is expected that Nenagh Agglomeration will have no significant adverse impact on habitats into which it discharges.

15. Toxicity Testing As part of Condition 4.11, toxicity testing was carried out on 4 relevant aquatic species from different trophic levels by standardised and internationally accepted procedures. This was completed by Aquatic Services Unit, Environmental Research Institute, Lee Road, Cork on behalf of North Tipperary County Council. The aquatic species used were

• Rainbow Trout • Waterflea • Duckweed • Vibrio fischeri (bacteria)

The results from the 4 bioassays performed on Nenagh WWTP Final Effluent indicate that the effluent was non-toxic across all of the species tested. Please find attached the full report on the testing by Aquatic Services Unit, Environmental Research Institute, Lee Road, Cork.

Section 7.1. Nenagh STP Upstream Test Results 2009.

StationName SampleLabCode SampleDate Ammonia as (N) Ammonium (NH4) BOD Chemical Oxygen Demand Chloride Coliform bacteria Conductivity @ 20°C Dissolved Oxygen (Meas urement) E-Coli Hardnessmg/L mg/L mg/L O2 mg/L O2 mg/L No./100mL µS/cm mg/L No./100mL mg/L CaCO3

Nenagh STP upstream 09470003 08/01/2009 0.024 0.03 2 16 17.94 435 12.94Nenagh STP upstream 09470093 03/02/2009 0.022 0.028 1 7 17.59 346 8.23Nenagh STP upstream 09470227 26/03/2009 0.02 0.03 2 5 17.67 275 11.3 220Nenagh STP upstream 09470273 16/04/2009 0.01 0.013 1 6 14.77 7270 338 11 305Nenagh STP upstream 09470330 07/05/2009 0.01 0.01 4 5 15.38 352 10.84Nenagh STP upstream 09470448 16/06/2009 0.037 0.05 2 11 17.05 410 9.22Nenagh STP upstream 09470582 21/07/2009 0.025 0.032 2 8 18.23 371 8.71Nenagh STP upstream 09470749 17/09/2009 BLD BLD 2 BLD 14.75 390 9.43Nenagh STP upstream 09470797 06/10/2009 0.156 0.201 4 9 15.79 381 8.48Nenagh STP upstream 09470913 05/11/2009 0.008 0.011 1 10 14.23 292 10.67Nenagh STP upstream 09471001 08/12/2009 0.027 0.035 2 BLD 15.6 344 10.62Nenagh STP upstream 09470649 11/08/2009 0.003 0.003 2 9 17.2 1460 373 9.89 400

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Section 7.1. Nenagh STP Upstream Test Results 2009.

SampleDate Nitrates (N03-N) Nitrites (NO2-N) Ortho-phosphate Ortho-phosphate as P pH Sulphate Suspended Solids Temperature Total Nitrogen (as N) Total Oxidised Nitrogen (TON as N) Total Phosphorus (as P)mg/L mg/L mg/L mg/L Units mg/L mg/L ºC mg/L mg/L mg/L

08/01/2009 3.74 BLD 0.07 0.02 8.05 9.41 3.6 3.1 3.73 0.0303/02/2009 2.66 BLD 0.05 0.02 7.88 7.83 8.4 5.2 2.66 0.0526/03/2009 3.07 BLD 0.04 0.01 8.1 9.23 0.4 9.6 3.06 0.0316/04/2009 2.07 BLD 0.03 0.01 8.02 8.94 0.8 10.7 2.07 0.0207/05/2009 1.83 0.01 0.19 0.06 8 8.24 6 10.2 1.84 0.116/06/2009 3.01 0.01 0.05 0.02 7.76 9.77 2.4 13.8 3.02 0.0321/07/2009 2.44 0.01 0.08 0.03 7.99 14.5 1.6 16.4 3 2.44 0.0317/09/2009 2.43 BLD 0.05 0.02 8.1 9.13 2.8 14.3 2.4 2.43 0.0706/10/2009 2.35 BLD 0.184 0.06 7.86 10.05 12.4 13.4 4.5 2.35 0.1905/11/2009 1.43 BLD 0.081 0.026 7.64 7.88 14 9 3.5 1.43 0.0508/12/2009 1.99 BLD 0.039 0.013 7.87 9.63 2.8 8.2 2.6 1.98 0.0211/08/2009 2.25 0.02 0.07 0.02 8.1 10.83 4 16.2 2 2.27 0.03

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Section 7.2. Nenagh STP Downstream Test Results 2009.

StationName SampleLabCode SampleDate Ammonia as (N) Ammonium (NH4) BOD Chemical Oxygen Demand Chloride Coliform bacteria Conductivity @ 20°C Dissolved Oxygen (Meas urement) E-Coli Hardnessmg/L mg/L mg/L O2 mg/L O2 mg/L No./100mL µS/cm mg/L No./100mL mg/L CaCO3

Nenagh STP downstream 09470004 08/01/2009 0.018 0.023 2 17 23.96 476 12.77Nenagh STP downstream 09470094 03/02/2009 0.059 0.076 2 11 19.3 364 7.84Nenagh STP downstream 09470228 26/03/2009 0.03 0.04 2 5 22.23 309 11.3 223Nenagh STP downstream 09470274 16/04/2009 0.02 0.029 1 2 17.72 8660 357 10.91 1330Nenagh STP downstream 09470331 07/05/2009 0.02 0.03 4 8 17.93 366 10.7Nenagh STP downstream 09470449 16/06/2009 0.137 0.177 2 4 19.69 423 9.2Nenagh STP downstream 09470583 21/07/2009 0.027 0.034 2 7 19.45 378 9.06Nenagh STP downstream 09470750 17/09/2009 0.01 0.013 2 4 19.15 410 9.71Nenagh STP downstream 09470798 06/10/2009 0.59 0.759 8 19 26.74 422 7.88Nenagh STP downstream 09470914 05/11/2009 0.013 0.017 2 10 15.49 308 10.26Nenagh STP downstream 09471002 08/12/2009 0.039 0.051 2 6 16.99 360 10.45Nenagh STP downstream 09470650 11/08/2009 0.002 0.003 2 8 18.61 6900 384 9.76 1100

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Section 7.2. Nenagh STP Downstream Test Results 2009.

SampleDate Nitrites (NO2-N) Ortho-phosphate Ortho-phosphate as P pH Sulphate Suspended Solids Temperature Total Nitrogen (as N) Total Oxidised Nitrogen (TON as N) Total Phosphorus (as P)mg/L mg/L mg/L Units mg/L mg/L ºC mg/L mg/L mg/L

08/01/2009 BLD 0.19 0.06 8.02 13.17 4 3 4.52 0.0703/02/2009 0.01 0.1 0.03 7.98 9.62 6.8 5.2 2.82 0.126/03/2009 BLD 0.1 0.03 7.99 13.63 1.2 9.4 3.02 0.0316/04/2009 0.01 0.06 0.02 7.99 11.21 3.2 10.8 2.1 0.0907/05/2009 0.01 0.2 0.07 8.01 9.41 4.8 10.2 1.86 0.0816/06/2009 0.02 0.11 0.03 7.95 13.09 3.2 14 3.03 0.0621/07/2009 0.01 0.09 0.03 8.1 15.87 4.4 15.5 3 2.53 0.0517/09/2009 0.01 0.09 0.03 8.14 13.05 2.8 13.5 2.3 2.51 0.0506/10/2009 0.08 0.678 0.221 7.83 24.12 24.8 13.1 5.3 3.07 0.3405/11/2009 BLD 0.09 0.029 7.74 9.18 16.8 9.4 3.3 1.52 0.0708/12/2009 BLD 0.051 0.017 7.85 10.77 0.4 8.2 3.2 2.17 0.0211/08/2009 0.02 0.09 0.03 8.1 11.09 0.8 17.2 2 2.3 0.03

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Section 2(i) Nenagh STP Plant Influent Test Results 2009.

StationName SampleLabCode SampleDate Ammonia as (N) Ammonium (NH4) BOD Chemical Oxygen Demand Chloride Nitrates (N03-N) Nitrites (NO2-N)mg/L mg/L mg/L O2 mg/L O2 mg/L mg/L mg/L

Nenagh STP (new) influent 09470001 08/01/2009 18.8 24.16 130 375 128.7 1.05 0.15Nenagh STP (new) influent 09470091 03/02/2009 5.33 6.85 30 105 78.05 3.55 0.1Nenagh STP (new) influent 09470225 26/03/2009 19.14 24.6 252 542 99.62 0.1 0.49Nenagh STP (new) influent 09470271 16/04/2009 21.79 28.01 229 706 107.7 BLD BLDNenagh STP (new) influent 09470328 07/05/2009 18.58 23.88 132 353 80.37 BLD 0.01Nenagh STP (new) influent 09470446 16/06/2009 20.6 26.47 185 477 103.6 0.06 0.01Nenagh STP (new) influent 09470580 21/07/2009 19.56 25.14 249 440 156.6 0.13 0.01Nenagh STP (new) influent 09470647 11/08/2009 28.2 36.25 375 834 123.78 0.88 BLDNenagh STP (new) influent 09470651 12/08/2009 32.24 41.57 362 965 155.46 0.06 0.01Nenagh STP (new) influent 09470666 13/08/2009 48.77 62.69 430 732 240.36 0.04 0.02Nenagh STP (new) influent 09470673 18/08/2009 25.16 32.34 148 752 179.16 BLD 0.01Nenagh STP (new) influent 09470675 19/08/2009 27.5 35.35 219 1004 151.91 BLD 0.01Nenagh STP (new) influent 09470689 20/08/2009 9.01 11.58 281 977 55.18 0.01 <0.01Nenagh STP (new) influent 09470692 25/08/2009 36.26 46.61 335 823 143.63 0.08 BLDNenagh STP (new) influent 09470694 26/08/2009 16.46 21.16 251 699 122.14 0.03 <0.01Nenagh STP (new) influent 09470702 27/08/2009 26.04 33.47 222 586 101.47 BLD 0.01Nenagh STP (new) influent 09470747 17/09/2009 23.24 29.87 219 471 112.3 0.09 0.01Nenagh STP (new) influent 09470795 06/10/2009 22.58 29.03 171 438 128.6 0.03 BLDNenagh STP (new) influent 09470911 05/11/2009 4.38 5.63 49 132 51.86 1.28 0.19Nenagh STP (new) influent 09470999 08/12/2009 7.48 9.61 160 186 56.96 1.73 0.29

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Section 2(i) Nenagh STP Plant Influent Test Results 2009.

SampleDate Ortho-phosphate Ortho-phosphate as P pH Sulphate Suspended Solids Temperature Total Nitrogen (as N) Total Oxidised Nitrogen (TON as N) Total Phosphorus (as P)mg/L mg/L Units mg/L mg/L ºC mg/L mg/L mg/L

08/01/2009 9.28 3.02 7.58 78.65 178 9.1 1.2 9.303/02/2009 2.24 0.73 7.69 47.65 32 4.2 3.65 1.2226/03/2009 8.77 2.86 7.54 73.97 353 10.2 0.59 5.7516/04/2009 9.9 3.23 7.61 72.81 447 11.1 BLD 8.507/05/2009 6.3 2.05 7.76 59.89 209 12.2 BLD 3.9516/06/2009 8.37 2.73 7.57 91.24 241 14.5 0.07 5.3521/07/2009 10.24 3.34 7.58 90.57 197 15.9 29 0.14 6.0511/08/2009 16 5.2 7.14 106.06 311 17.8 31 912/08/2009 20.08 6.55 7.6 125.54 536 16 0.07 NT13/08/2009 24.74 8.06 7.75 98.98 419 14.8 0.05 9.418/08/2009 12.52 4.08 7.31 96.55 441 14.3 BLD 6.119/08/2009 15.6 5.09 7.27 71.56 520 18 <0.01 9.720/08/2009 9.65 3.15 7.03 51.17 749 17.1 0.01 6.925/08/2009 14.51 4.73 7.41 91.27 464 17.9 0.07 8.726/08/2009 10.04 3.27 7.27 82.98 357 18.1 0.03 7.427/08/2009 10.4 3.39 7.39 90.06 385 15.3 <0.01 6.817/09/2009 10.11 3.3 7.64 94.16 341 15 30.9 0.09 7.606/10/2009 6.98 2.274 7.23 98.6 488 13.7 30.4 0.03 405/11/2009 1.964 0.64 7.27 53.96 61 13.6 11.5 1.47 1.6608/12/2009 2.19 0.714 7.22 53.62 99 10.5 15 2.03 1.44

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Section 1.0 Nenagh STP Final Effluent Test Results 2009.

StationName SampleLabCode SampleDate Ammonia as (N) Ammonium (NH4) Arsenic Atrazine Barium BOD Boron Cadmium Chemical Oxygen Demand Chloride Chromium Conductivity @ 20°C Copper Cyanidemg/L mg/L µg/L µg/L µg/L mg/L O2 µg/L µg/L mg/L O2 mg/L µg/L µS/cm µg/L µg/L

Nenagh STP (new) final effluent 09470002 08/01/2009 0.044 0.057 5 41 127.2Nenagh STP (new) final effluent 09470092 03/02/2009 0.018 0.023 4 28 57.09Nenagh STP (new) final effluent 09470226 26/03/2009 0.355 0.456 6 28 104.6Nenagh STP (new) final effluent 09470272 16/04/2009 0.521 0.67 0.6 <0.01 10.3 7 70 <0.1 30 107.9 <1 9.4 <5Nenagh STP (new) final effluent 09470329 07/05/2009 2.25 2.89 5 18 84.8Nenagh STP (new) final effluent 09470447 16/06/2009 2.08 2.67 4 27 71.57Nenagh STP (new) final effluent 09470581 21/07/2009 0.098 0.126 3 25 91.54Nenagh STP (new) final effluent 09470648 11/08/2009 0.176 0.226 0.5 <0.01 9.9 5 90 <0.1 29 122.95 <1.0 NT 0.01 <5.0Nenagh STP (new) final effluent 09470652 12/08/2009 0.46 0.59 3 14 134.09Nenagh STP (new) final effluent 09470667 13/08/2009 0.45 0.578 3 27 138.87Nenagh STP (new) final effluent 09470674 18/08/2009 0.292 0.375 2 32 109.77Nenagh STP (new) final effluent 09470676 19/08/2009 0.042 0.054 2 22 124.06Nenagh STP (new) final effluent 09470690 20/08/2009 0.213 0.274 3 15 107.9Nenagh STP (new) final effluent 09470693 25/08/2009 0.14 0.18 2 19 84.67Nenagh STP (new) final effluent 09470695 26/08/2009 1.47 1.89 2 7 118.8Nenagh STP (new) final effluent 09470703 27/08/2009 1.83 2.35 4 34 111.62Nenagh STP (new) final effluent 09470748 17/09/2009 0.266 0.342 5 22 110.9Nenagh STP (new) final effluent 09470796 06/10/2009 0.076 0.097 6 10 86.1Nenagh STP (new) final effluent 09470912 05/11/2009 0.006 0.007 4 10 47.51Nenagh STP (new) final effluent 09471000 08/12/2009 0.136 0.175 6 23 49.05

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SampleDate Dichloromethane Fluoride Hardness Lead Mercury Nickel Nitrates (N03-N) Nitrites (NO2-N) Oils, Fats & Grease Ortho-phosphate Ortho-phosphate as P PAH (Polycyclic Aromatic Hydrocarbons) pH Phenolsµg/L µg/L mg/L CaCO3 µg/L µg/L µg/L mg/L mg/L mg/L mg/L mg/L µg/L Units µg/L

08/01/2009 14.68 0.12 2.25 0.73 7.3503/02/2009 7.75 0.02 0.55 0.18 8.0526/03/2009 262 7.1 0.17 1 1.58 0.52 7.3116/04/2009 <5 100 <0.3 <0.02 2.9 2.53 0.16 1.36 0.44 <0.01 7.98 30207/05/2009 1.39 0.14 1.32 0.43 7.4816/06/2009 2.13 0.31 2.4 1.72 0.56 7.5721/07/2009 6.63 0.2 1.57 0.51 7.7111/08/2009 <5.0 300 <0.3 <0.02 3.6 2.65 0.31 1.01 0.33 0.08 8.01 1612/08/2009 0.7 0.23 1.2 0.39 7.9113/08/2009 0.46 0.18 1.27 0.42 7.8418/08/2009 0.5 0.17 1.28 0.42 8.0119/08/2009 0.99 0.11 1.27 0.41 8.2820/08/2009 0.53 0.1 1.63 0.53 7.9425/08/2009 2.77 0.4 0.94 0.31 7.826/08/2009 3.95 0.61 1.61 0.52 7.7427/08/2009 2.74 0.5 2.04 0.67 7.6617/09/2009 5.92 0.88 10.5 1.18 0.38 7.9206/10/2009 6.53 0.19 1.183 0.386 7.805/11/2009 4.42 0.08 <1 0.786 0.256 7.4308/12/2009 7.77 0.38 0.442 0.144 7.55

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SampleDate Selenium Simazine Sulphate Suspended Solids Temperature Toluene Total Nitrogen (as N) Total Oxidised Nitrogen (TON as N) Total Phosphorus (as P) Toxicity Tributyltin Xylenes Zincµg/L µg/L mg/L mg/L ºC µg/L mg/L mg/L mg/L T.U. µg/L µg/L µg/L

08/01/2009 92.02 13.2 6.8 14.8 0.7403/02/2009 58.89 9.2 2.3 7.77 0.4326/03/2009 91.29 12.4 11.6 7.27 0.8116/04/2009 <0.2 <0.01 87.35 2.4 10.9 <0.1 3.8 2.69 0.72 <0.02 <0.1 20.907/05/2009 79 6.4 12.5 1.54 0.5116/06/2009 92 5.6 14.6 2.44 0.721/07/2009 107.2 7.2 17.3 8 6.82 0.5811/08/2009 <0.2 <0.01 134.99 10.4 17.4 <0.1 4 2.96 0.47 <0.02 <0.1 32.312/08/2009 173.24 4 16.5 NT 0.93 NT13/08/2009 116.67 6.4 14.9 NT 0.64 0.518/08/2009 109.96 1.2 14.4 0.67 0.5219/08/2009 96.85 2.8 18.5 1.1 0.520/08/2009 91.27 5.6 17.5 0.63 0.5625/08/2009 88.87 2.4 16.3 3.17 0.3926/08/2009 101.97 2.8 17.8 4.55 0.6327/08/2009 10.04 4.4 15.4 3.24 0.7617/09/2009 121.9 8.4 13.9 9.4 6.8 0.5906/10/2009 121.5 10 13.5 13.7 6.72 0.6305/11/2009 55.19 9.6 12.5 6.7 4.5 0.4608/12/2009 62.56 6.4 10.5 9.8 8.15 0.22 Non-toxic

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ELRA - D0027-01 Environmental Liability Risk Assessment

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North Tipperary County Council

Environmental Liability Risk Assessment & Statement of Measures for Nenagh Agglomeration.

2010

Urban Waste Water Discharge Licence D0027-01


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Table of Contents

1 INTRODUCTION……………………………………………………..3

1.1 Background………………………………………………………….3

2 ENVIRONMENTAL SENSITIVITY AND RISK ASSESSMENT...4

2.1 Sensitivity of Receiving Waters…………….....................................4 2.2 Groundwater Protection……………………………………………..4 2.3 Protected Ecological Sites and Species……………………………..4 2.4 Human Health……………………………………………………….4

3 RISK PREVENTION/MITIGATION………………………………..9 4 STATEMENT OF MEASURES……………………………………...9 5 FINANCIAL PROVISIONS………………………………………….11

5.1 Estimation of Remediation Costs…………………………………...11 5.2 Details of Financial Provision/Insurance………………………….. 11


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1. Introduction This Environmental Liability Risk Assessment relates to the agglomeration of Nenagh Town and Environs. This report has been prepared in compliance with Condition 7.2 of Licence No. D0027-01, which require the submission of:

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

• The financial provision in place in relation to the underwriting of costs for

remedial actions following anticipated events (including closure) or accidents/incidents, as may be associated with discharges or overflows from the waste water works.

• Environmental Liabilities Risk Assessment (ELRA) to address the liabilities

from present or planned discharges, within twelve months of the data of grant of the licence.

1.1 Background Nenagh Agglomeration has a population equivalent (P.E.) of approximately 18,400. This population is served, in terms of waste water infrastructure, by a combined sewer network. The wastewater works comprises a network of sewers, pumping stations, associated rising mains and Nenagh WWTP. Nenagh WWTP is located near Kyleeragh Bridge on the Old Birr Road, Nenagh, on the western bank of the Nenagh River. The WWTP is divided into two interconnected parts, the “new plant” with a design treatment capacity of 13,000 P.E., is located north of the Old Birr Road, and the “old plant” with a design treatment capacity of 5,000 P.E. (currently in reserve/standby mode) is located to the south of the road. Landfill leachate is imported to the WWTP from Ballaghveny Landfill (Reg. No. W0078-03). Nenagh WWTP also processes sewage sludge from smaller WWTPs in North Tipperary. Nenagh received its Waste Water Discharge Licence (WWDL) from the Environmental Protection Agency on 25 September 2008. The Nenagh River from “Downstream of Nenagh Sewage Outfall to its confluence with Lough Derg” is designated as a sensitive water under the Urban Waste Water Treatment Regulations, 2001(S.I. No. 254 of 2001). Under the conditions of the WWDL, Nenagh WWTP is required to comply with Total Phosphorus (1 mg/l) limit. This has been achieved. All monitoring sampling test results taken of the primary discharge since the WWDL was issued were within the Emission Limit Values for Nenagh as set out in Schedule A of the WWDL.


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2. Environmental Sensitivity and Risk Assessment. The main considerations in relation to the receiving waters for the primary discharge been identified and given a designated score and are set out in Table 1. 2.1. Sensitivity of Receiving Waters. EPA water quality monitoring station No. 25N010500, which is located at Tyone, Nenagh and is located upstream of Nenagh Agglomeration, has a current (2008) EPA biological Q rating of the Nenagh River of Q3-4 (slightly polluted). The EPA water quality monitoring station No. 25N010700, which is located at the bridge downstream of Nenagh Bridge, and is located downstream of Nenagh Agglomeration, has a current (2008) EPA biological Q rating of the Nenagh River of Q3-4. 2.2 Groundwater Protection Nenagh Agglomeration is situated on poorly productive bedrock. It is situated on a locally important aquifer and is moderately productive only in local zones. GSI (Geological Survey Ireland) mapping indicates that vulnerability is high to low, from contaminants released at depths of 1m to 2m below the ground surface, although it should be noted that only an interim survey took place. Geological mapping indicates that the Nenagh WWTP does not lie within a groundwater Source Protection Area (SPA), as defined by the GSI. There are no SPAs recorded within 1km of Nenagh WWTP. 2.3 Protected Ecological Sites and Species (nearest receptor distance from any discharge). Nenagh Agglomeration discharges into the Nenagh River, which is designated as Nutrient Sensitive Water Body, but is not considered a Protected Ecological Site. It is not a NHA, SPA or SAC. Nenagh Agglomeration does not have a significant adverse effect on the Nenagh River. 2.4 Human Health There are no identified abstractions downstream of the primary discharge on the Nenagh River. There are no designated bathing sites on the Nenagh River.


5

Table 1: Environmental Sensitivity Environmental Attribute

Attribute Score

Designated Score

Comment

Sensitivity of Receiving Water Class A (Q5, Q4-5, Q4)

3

Class B (Q3-Q4)

2 2 Class B. New Assessment due 2011

Class C (Q3, Q2-3)

1

Class D (Q2, Q1-2, Q1) 0 Designated Costal & Estuarine Waters

2

Potentially Eutrophic Coastal & Estuarine

1

Groundwater Protection Regionally Important Aquifer

2

Locally Important Aquifer

1 1 Locally Important Aquifer

Poor Aquifer

0

Vulnerability Rating - Extreme

3

Vulnerability Rating - High

2 2 Vulnerability ranges from High to Low

Vulnerability Rating - Moderate

1

Vulnerability Rating - Low

0

Protected Ecological Sites and Species (Shortest distance from any discharge) Discharge within or directly bordering a designated site

2

<1km 1 >1km 0 0 None Human Health Discharge within or directly bordering a designated shellfish area

0 - 5 km 1 >5 km 0 0 Freshwater Designated Bathing


6

Water Within 0-5 km 1 >5 km 0 0 None Drinking Water Source

Within 0-10 km 1 >10km 0 0 None Environmental Sensitivity Score 5


7

Table 2: Risk Assessment Form

Risk I.D.

Process Potential hazards Environmental Effect

Severity Rating

Basis of Severity

Occurrence Rating

Basis of Occurrence

Risk Score (Severity x Occurrence)

I Receives Landfill Leachate from Ballaghveny Landfill

This leachate often contains high levels of ammonia. There is a potential for ammonia shock loading on Nenagh WWTP, and subsequent high levels of Ammonia in the final plant effluent. Leachate may contain possible hazardous substances not metabolised by the treatment plant.

Possibility of High Levels of Ammonia in final effluent. Also possible toxic effects from landfill leachate.

4 Could have a significant impact on Nenagh River.

3 No previous problems with Landfill Leachate

12

II Chemical Dosing Ferric Sulphate

Spill during deliveries.

Spill on site, groundwater contamination, subsequent impact on watercourses.

3 Ferric Sulphate, high toxicity

2 Proper bunds in place. Valves inside bunds.

6

III Stormwater flooding of plant

Extreme stormwater and weather conditions overwhelms plant leading to solids carryover from settlement tanks.

Reduced efficiency of plant with reduced treatment of wastewater.

3 Carryover of solids into river system

3 Plant rarely flooded, due to plant and network stormwater overflows.

9

IV Groundwater Infiltration of Sewer Network leading to higher hydraulic loading on plant.

High hydraulic loading leading to solids carryover from settlement tanks.

Reduced efficiency of plant with reduced treatment of wastewater.

3 Carryover of solids into river system

3 Sewers in good condition generally.

9


8

Table 3:Risk Matrix

Occurrence V.High 5 High 4 Medium 3 III, IV I Low 2 II V.Low 1

Trivial Minor Moderate Major Massive 1 2 3 4 5

Severity

These are considered to be high-level risks requiring priority attention. These risks have the potential to be catastrophic and as such should be addressed quickly.

These are medium-level risks requiring action, but are not as critical as a red coded risk.

Green (light and dark green) – These are lowest-level risks and indicate a need for continuing awareness and monitoring on a regular basis. Whilst they are currently low or minor risks, some have the potential to increase to medium or even high-level risks and must therefore be regularly monitored, and if cost effective mitigation can be carried out to reduce the risk even further, this should be pursued.


9

3. Risk Prevention/Mitigation The risk matrix above indicates that there is no high level of risk classification for Nenagh WWTP. The management of Nenagh Waste Water Works continually reviews the operation of the works with a view to reducing any risks to the environment. 4. Statement of Measures The measures to be taken by North Tipperary County Council are outlined in Table 4 below. Measures are in place within Nenagh Waste Water Works are adequate to maintain the discharge at a quality that complies with the licence conditions and does not significantly impact on the conservation objectives of the Nenagh River. Table 4: Statement of Measures

Risk I.D.

Risk Score

Mitigation measure to be taken

Outcome Action Date for Completion

Contact Person

I 12 New storage tank for the consistent pumping of landfill leachate into Nenagh WWTP.

Reduce the risk of shock loading of ammonia.

Design and purchase of new storage tank specifically for landfill leachate.

December 2010. Will depend on resources available.

Executive Engineer, West Area, Water Services.

II 9 Staff member to accompany ferric sulphate delivery lorry at all stages of delivery to ensure no spillage.

Reduce risks of spills

Write Formal SOP for delivery of chemicals and oblige contractors to use

July 2010 Executive Engineer, West Area, Water Services.

III 9 Reduce risk of flooding at plant

Reduce risk of solids carryover

Maintain a MLSS of approximately 3000mg/l and

This practise is ongoing for many

Executive Engineer, West Area,


10

from settlement tanks.

maintain a regular low sludge blanket in the settlement tanks to prevent a solid carryover in the event of severe flooding

years. Water Services.

IV 9 Reduce risk of flooding at plant

Reduce risk of solids carryover from settlement tanks.

Regularly carry out CCTV surveys of the sewer network and replace badly damaged sewer main.

This practise is ongoing for many years

Executive Engineer, West Area, Water Services


11

5 FINANCIAL PROVISIONS 5.1. Estimation of remediation costs Table 5 below outlines the estimated costs of remediation for different categories of events. Table 5: Risk Classification Table Rating Severity Category Description Cost of

Remediation 1 Trivial No damage or

negligible change to the environment.

€1,000

2 Minor Minor impact/localised or nuisance.

€5,000

3 Moderate Moderate damage to the environment

€10,000

4 Major Severe damage to local environment

€100,000

5 Massive Massive damage to a large area, irreversible in medium term

€1,000,000

5.2. Details of Financial Provision/Insurance. In order to offset the risk to the environment, the Council is currently in negotiation with an insurance company to take out an Environmental Liabilities Directive Insurance Policy. A copy of the policy document in its entirety will be sent to the Agency as soon as it is completed.

Report on the WWD Toxicity Testing for North Tipperary County Council for the Nenagh WWTP

December 2009

Licence Discharge Number D0027-01 Sample Date-08/12/2009

Report prepared by

Aquatic Services Unit, Environmental Research Institute.

Lee Road. Cork

2

Introduction

Toxicity testing was requested by North Tipperary Council for a final waste water effluent sample at the Nenagh WWTP facility. This testing was requested as part of WWD licensing requirements for the facility. Four aquatic species from different trophic levels were selected for the testing namely rainbow trout (Onchorhynchus mykiss), waterflea (Daphnia magna), duckweed (Lemna minor), and bacteria (Vibrio fischeri). Testing commenced on 8th, 2009 and finished on December 14th, 2009. Methodology

The effluent sample was collected on December 8th, 2009 and transported to the Aquatic Services Unit (ASU) by ASU staff on the same day. The sample had a temperature of 11.1ºC on arrival and was then immediately placed in a refrigerator at 4 ºC until required for testing. Rainbow trout bioassay

The trout bioassay was carried out following standard methods as described in US EPA Whole Effluent Testing Guidelines (US EPA, 2002). The effluent was tested for toxicity at the following concentrations 6.25, 12.5, 25, 50, and 100. Twenty fish were tested for each concentration, the fish were added into 2 replicates of ten fish per concentration. Testing was carried out in a constant temperature room at a temperature of 12 ºC ± 2 throughout the test. A light regime of 12 hours dark/12 hours light was used throughout the testing period. The test duration was 96 hours. Mains water de-chlorinated by means of aeration was used as control and dilution water. The fish were sourced from Goat Bridge Trout Farm, Co. Kilkenny and were approximately 50 days old at the time of testing. All of the test chambers and controls had to be aerated 48 hours following test initiation as the dissolved oxygen had fallen to less than 6 mg/L in the effluent sample. Aeration was carried out following US EPA protocols. Daphnia magna Bioassay

The Daphnia bioassay was carried out following standard methods as described in US EPA Whole Effluent Testing Guidelines (US EPA, 2002). The effluent was tested for toxicity at the following concentrations 6.25, 12.5, 25, 50, and 100%. Twenty Daphnia neonates (animals less than 24 hours old) were tested for each concentration. These animals were added into 4 replicates of five animals per test chamber for each concentration. Testing was carried out in a constant temperature room at a temperature of 20 ºC ± 2 throughout the test. A light regime of 16 hours light/8 hours dark was used throughout the testing period. The test duration was 48 hours. Mains water de-chlorinated by means of aeration was used as control and dilution water. The D. magna were obtained from in house cultures at ASU.

3

Duckweed Bioassay

The Duckweed bioassay was carried out following standard methods as described in Standard Methods for the Examination of Water and Wastewater, (APHA, 2005). The effluent was tested for toxicity at the following concentrations, 6.25, 12.5, 25, 50, and 100%. Four replicates of 100mls each inoculated with 12 fronds of duckweed were tested for each concentration. A concurrent positive control containing chromate at 20mg/L was also was carried out to determine the health and sensitivity of the duckweed plants Testing was carried out in a constant light growth room at a temperature of 22 ºC ± 2 throughout the test. The test duration was 96 hours. Control and dilution water was prepared as described in standard methods (APHA, 2005). The duckweed was obtained for the test from on-going cultures at the Department of Zoology, Ecology, and Plant Sciences in University College Cork Vibrio fischeri bacteria bioassay using Microtox system.

The luminescent bacteria Vibrio fischeri are used exclusively in the Microtox system. Testing was carried out following the 81.9% basic test AZUR guidelines (Azur Environmental, 1995). The concentrations of effluent tested ranged from 2.6% to 81.90%. Two replicates were used for each concentration tested. A concurrent reference toxicant bioassay was also carried out to determine the health and suitability of the bacteria. Statistical Analyses

Statistical analyses to generate LC50 (Lethal Concentration to cause 50 percent mortality) data and multiple comparison data were performed using Toxcalc version 5.0.32 statistical software package (Tidepool Scientific).

4

Results and Discussion Rainbow trout bioassay results

The test was considered valid as there was greater than 90% survival in the controls (US EPA, 2002). No toxicity was recorded in any of the test concentrations with 100% survival observed in all of the test chambers. There was no significant difference in survival between the control water and the 100% effluent. No LC50 values were generated as the effluent was non-toxic to rainbow trout. Daily water quality measurements for the bioassay are presented in Appendix 1. Results of the bioassay are displayed in Figure 1.

96 Hr Rainbow Trout Bioassay

0

20

40

60

80

100

Control 6 12 25 50 100

Effluent Concentration (%)

Sur

vivi

al (

%)

Figure 1 Average survival of rainbow trout after 96 hours in a concentration series of Nenagh WWTP effluent.

5

Daphnia magna bioassay results

This test was deemed to be valid given that there was greater than 90% survival in the controls indicating that the animals and testing conditions were satisfactory (US EPA, 2002). Survival across the concentration series of effluent ranged between 95% and 100% demonstrating that the effluent is non-toxic to D. magna. No LC50 value was generated for this bioassay due to the non-toxic nature of the effluent. Results of this bioassay are displayed in Figure 2. Water quality measurements in the test chambers remained within normal limits for the duration of the bioassay. These data are presented in Appendix 2. A concurrent bioassay was carried out using Zinc sulphate as a reference toxicant to determine the sensitivity of the current batch of test organisms. This bioassay produced an LC50 of 1.36 mg/L for zinc sulphate. This value is similar to what has been recorded in previous in house studies and reported in the literature (US EPA 2007).

48 Hr Daphnia magna Bioassay

0

20

40

60

80

100

Control 6 12 25 50 100


Sur

vivi

al (

%)

Figure 2 Average survival of Daphnia magna after 48 hours in a concentration

series of Nenagh WWTP effluent. Error bars represent standard deviation of the mean.

Lemna minor Bioassay results

The Lemna bioassay was deemed to be valid as there was greater than a twofold increase in the number of fronds in the controls over the 96-hour period (APHA, 2005). No toxicity in terms of a decrease in of the specific growth rate was observed in any of the effluent concentrations tested. A no observed effect concentration (NOEC) of 100 % was observed for the Nenagh effluent. Furthermore

6

no signs of chlorosis or abnormal frond development were observed in either the control or the effluent test chambers. Results from this bioassay are presented in Figure 3.

A concurrent positive control using 20mg/L of chromate ion was also tested. This concentration produced a 63 % inhibitory effect on duckweed growth. This inhibitory effect is in agreement with values reported in the APHA protocol for duckweed sensitivity to the chromate ion and indicates that the plants used in the current round of testing were suitable for testing. (APHA, 2005).

96 Hr Lemna minor Bioassay

0

20

40

60

Control 6 12 25 50 100


No.

of f

rond

s

Figure 3 Growth of the Duckweed (Lemna minor) after 96 hours in a concentration series of Nenagh WWTP effluent. Error bars represent standard deviation of the mean.

7

Microtox results.

The Microtox bioassay carried out on December 11, 2009 was deemed to be valid. A reference toxicant test was carried out before actual testing of samples took place to ensure that the bacterium and reagents were suitable for testing. The reference toxicant using Zinc Chloride determined an LC50 of 4.9 mg/L after 15 minutes exposure. This is within the guideline range of 3-10 mg/L as specified by the Microtox manufacturer (Azur Environmental, 1995). These data are presented in Appendix 4.

No toxicity was observed between the controls and throughout the effluent concentration series. No significant decrease in light production was observed in any of the concentrations during the test. Some light stimulation was observed in all of the concentrations tested as compared to the control. This light stimulation has been shown to occur in other non-toxic samples and is an artefact of testing method. ASU have tested non-toxic blank samples (containing de-ionized water and osmotic adjusting solution) and recorded similar results. Based on the supporting data from the other bioassays performed on this effluent sample it appears that this sample is also non-toxic using the Microtox system. The data for the effluent test are presented in Figure 4.

Microtox Effluent Bioassay

0

20

40

60

80

100

120

0 20 40 60 80 100


Rel

ativ

e Li

ght P

rodu

ctio

n (%

)

Effluent

Control

Figure 4 Plot of the Microtox results for Nenagh WWTP effluent sample on 11/12/09. Values represent light production relative to the controls. The highest concentration of effluent tested was 81.9%.

8

Summary and Conclusions

The results from the 4 bioassays performed on the Nenagh WWTP final effluent indicate that the sample was non-toxic across all of the species tested. All of the bioassays performed were deemed to be valid as they meet all of the criteria as specified in the guidelines. References APHA, 2005. Standard methods for the examination of water and wastewater. 21st edition. American Public Health Association, Washington, DC,USA. Azur Environmental, 1995. Microtox Acute Basic Test Procedures. Azur Environmental ,. Carlsbad, California, USA. US EPA, 2002. Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition. US EPA, Washington DC, USA. U.S EPA, 2007. ECOTOX User Guide: ECOTOXicology Database System. Version 4. http:/www.epa.gov/ecotox.

9

Appendix 1- Water Quality Measurements for Rainbow Trout Bioassay

96 Hour Fish Bioassay 08/12/09North Tipp CoCo

Nenagh WWTP EffluentConcentration (%) Survival D.O (mg/L) pH Cond. ( µS/cm) Temp

0hrs 24hrs 48hrs 72hrs 96hrs 0hrs 24hrs 48hrs 72hrs 96hrs 0hrs 24hrs 48hrs 72hrs 96hrs 0hrs 24hrs 48hrs 72hrs 96hrs 0hrs 24hrs 48hrs 72hrs 96hrsControl A 10 10 10 10 10 10.8 9.3 6.2 7.2 8.1 7.66 7.71 6.82 6.96 7.15 146 147 148 149 152 13.6 13.7 13.7 13.6 13.8Control B 10 10 10 10 10 10.8 9.4 7.6 8.3 7.57 7.55 7.46 7.45 7.43 7.15 146 147 148 149 152 13.6 13.7 13.7 13.6 13.8

6A 10 10 10 10 10 11.1 9.2 5.8 7.2 7.1 7.53 7.68 7.77 7.59 7.33 195 196 196 196 200 11.5 13.1 13.5 13.8 14.06 B 10 10 10 10 10 11.1 9.2 7 7.2 7.1 7.53 7.68 7.35 7.59 7.33 195 196 196 196 200 11.5 13.1 13.5 13.8 14.012A 10 10 10 10 10 11 9.5 5.9 7.4 8.1 7.57 7.55 7.46 7.45 7.43 239 240 242 244 244 11.7 13.1 13.6 13.8 14.112B 10 10 10 10 10 11 9.5 5.9 7.4 8.1 7.57 7.55 7.46 7.45 7.43 239 240 242 244 244 11.7 13.1 13.6 13.8 14.125A 10 10 10 10 10 10.7 8.8 5.3 6.8 6.2 7.76 7.5 7.45 7.45 7.44 322 324 323 325 321 12.0 13.2 13.7 13.7 14.225B 10 10 10 10 10 10.7 8.8 5.3 6.8 6.2 7.76 7.5 7.45 7.45 7.44 322 324 323 325 321 12.0 13.2 13.7 13.7 14.250A 10 10 10 10 10 9.9 7.5 5.3 6.2 6.2 7.73 7.56 7.53 7.52 7.67 489 491 490 493 494 13.5 13.5 13.9 13.9 14.250A 10 10 10 10 10 9.9 7.5 5.3 6.2 6.2 7.73 7.56 7.53 7.52 7.67 489 491 490 493 494 13.5 13.5 13.9 13.9 14.2

100A 10 10 10 10 10 9.1 7.2 5.4 7.0 6.81 7.78 7.84 8.87 8.00 8.01 809 810 810 811 811 13.7 13.9 14.1 13.9 14.5100B 10 10 10 10 10 9.1 7.6 5.4 7.0 6.81 7.78 7.84 8.87 8.00 8.01 809 810 810 811 811 13.7 13.9 14.1 13.9 14.5

Date

NotesDay 0 Initiated at 16.00, Fish approx 50 days old sourced from Goat Bridge trout farm Co. Kilkenny.

24hrs

48hrs Supplied aeration to all chambers due to low DO levels in effleunt chambers

72hrs

96hrs Terminated at 13.30

Testing performed by Aquatic Services Unit, ERI Building, Lee Rd., Cork

10

Appendix 2- Water Quality Measurements for Daphnia magna Bioassay 48 Hour Daphnia Bioassay 09/12/09

N Tipp CoCoNenagh WWTP Effluent

Concentration (%) Survival D.O (mg/L) pH Conductivity(µS/cm) Temp (ºC)0hrs 24hrs 48hrs 0hrs 24hrs 48hrs 0hrs 24hrs 48hrs 0hrs 24hrs 48hrs 0hrs 24hrs 48hrs

Control A 5 5 5 10.8 9.0 7.36 7.40 146 147 19.0 21.0 21.0Control B 5 5 5Control C 5 5 5Control D 5 5 5

6.25A 5 5 5 10.2 7.9 7.72 7.75 192 195 19.0 21.0 21.06.25B 5 5 46.25C 5 5 56.25D 5 5 512.5A 5 5 5 11.0 6.5 7.68 7.69 236 236 19.0 21.0 21.212.5B 5 5 512.5C 5 5 412.5D 5 5 525A 5 5 5 10.9 4.8 7.71 7.81 319 322 19.1 21.0 21.025B 5 5 525C 5 5 525D 5 5 550A 5 5 5 11.0 2.8 7.79 7.85 483 485 19.2 21.0 21.250A 5 5 550A 5 5 550B 5 5 4

100A 5 5 5 11.2 1.1 7.90 7.98 808 809 19.8 21.0 20.9100B 5 5 5100C 5 5 5100D 5 5 5

NotesDay 0 Initiated at 15.00 animals less than 24hrs old on initiation24hrs

48hrs Terminated at 16.50


11

Appendix 3- Water Quality Measurements for Lemna minor Bioassay

96 Hour Lemna Bioassay 10/12/09 Water Quality Measurements- North Tipp CoCo

Nenagh WWTP EffluentConcentration (%) Conductivity D.O (mg/L) pH Temp

0hrs 24hrs 48hrs 72hrs 96hrs 0hrs 24hrs 48hrs 72hrs 96hrs 0hrs 24hrs 48hrs 72hrs 96hrs 0hrs 24hrs 48hrs 72hrs 96hrsControl 1912 1873 8.4 8.4 7.63 7.14 20.5 23.5

6% 1942 1883 8.6 8.6 7.63 7.70 20.1 23.512% 1973 1918 8.5 8.4 7.63 7.6 20.2 23.525% 2040 1953 8.7 8.5 7.63 7.84 20.0 23.550% 2180 2130 8.8 8.3 7.64 8 19.9 23.5100% 2460 2300 9.5 8.6 7.69 8.48 19.5 23.5

NotesDay 0 Test Initiated at 15.00

24hrs

48hrs

72hrs

96hrs Test terminated at 17.30


12

Appendix 4- Microtox Reference Toxicant Bioassay

Microtox Zinc Chloride Bioassay

0

10

20

30

40

50

60

70

80

90

0 20 40 60 80 100

Concentration (mg/L)

Ligh

t Inh

ibiti

on (

%)

5 Min Data

15 Min Data

Plot of light inhibition relative to the controls versus zinc chloride concentration after 5 and 15 minutes exposure.

13

The toxicity testing carried out for this report complies with internationally accepted guidelines. The results of these toxicity tests contained in this report are deemed valid under these guidelines. Signed _____________________________ David Gillespie MSc (Toxicology)

Nenagh AER 2009 - tipperarycoco.ie · Section 7.1. Nenagh STP Upstream Test Results 2009. StationName SampleLabCode SampleDate Ammonia as (N) Ammonium (NH4) BOD Chemical Oxygen Demand

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