Annual Environmental Report 2015

Transcription

1 Annual Environmental Report 2015 Agglomeration Name: Licence Register. D Blessington

2 Table of Contents Section 1. Executive Summary and Introduction to the 2015 AER Summary report on 1 Section 2. Monitoring Reports Summary Summary report on monthly influent monitoring Discharges from the agglomeration Ambient monitoring summary Data collection and reporting requirements under the Urban Waste Water Treatment Directive Pollutant Release and Transfer Register (PRTR) - report for previous year 4 Section 3 Operational Reports Summary Treatment Efficiency Report Treatment Capacity Report Extent of Agglomeration Summary Report Complaints Summary Reported Incidents Summary Sludge / Other inputs to the WWTP 8 Section 4. Infrastructural Assessments and Programme of Improvements Storm water overflow identification and inspection report Report on progress made and proposals being developed to meet the improvement programme requirements. 9 Section 5. Licence Specific Reports Priority Substances Assessment Drinking Water Abstraction Point Risk Assessment Shellfish Impact Assessment Report Toxicity / Leachate Management Toxicity of the Final Effluent Report Pearl Mussel Measures Report Habitats Impact Assessment Report 13 Section 6. Certification and Sign Off 14 Section 7. Appendix 15 i Irish Water

3 Section 1. Executive Summary and Introduction to the 2015 AER 1.1 Summary report on 2015 This Annual Environmental Report has been prepared for D , Blessington, in County Wicklow in accordance with the requirements of the wastewater discharge licence for the agglomeration. There are no Specified assessments required in the 2015 AER. The agglomeration is served by a wastewater treatment plant with a Plant Capacity PE of 6,000. The treatment process includes the following:- Preliminary treatment (including screening / grit removal) Secondary treatment extended aeration activated sludge. Chemical dosing for phosphorus removal The final effluent from the Primary Discharge Point was non-compliant with the Emission Limit Values in The following parameters exceeded the emission limit values in 2015:- Ammonia The ELV for suspended solids was exceeded on one occasion, but did not exceed the ELV with Condition 2 Interpretation included. 706,580 kg sludge (86,260 kgs dry solids) was removed from the wastewater treatment plant as dewatered sludge cake and was transferred to D0012 Wicklow Sludge Treatment Centre for thermal drying. 91,770 kg sludge (10,880 kgs dry solids) was removed for lime stabilisation and 74,280 kg sludge (9,050 kgs dry solids) was removed for anaerobic digestion. There were no major capital or operational changes undertaken in An Annual Statement of Measures is included in Appendix Irish Water

4 Section 2. Monitoring Reports Summary 2.1 Summary report on monthly influent monitoring Table Influent Monitoring Summary BOD COD SS TP TN Hydraulic Loading (m 3 /d) Organic Loading (PE/day) Number of Samples Annual Max ,118 8,771 Annual Mean ,790 Significance of results The annual mean hydraulic loading is less than the peak Treatment Plant Capacity as detailed further in Section 3.2. The annual maximum hydraulic loading is less than the peak Treatment Plant Capacity as detailed further in Section 3.2. The annual mean organic loading is less than the Treatment Plant Capacity as detailed further in Section 3.2. The annual maximum organic loading is greater than the Treatment Plant Capacity as detailed further in Section Irish Water

5 2.2 Discharges from the agglomeration Table Effluent Monitoring Summary BOD COD WWDL ELV (Schedule A) TSS Ammonia Ortho-P to 9 ELV with Condition 2 Interpretation included to 9 ph Comment Number of sample results Number of sample results above WWDL ELV Number of sample results above ELV with Condition 2 Interpretation included Annual Mean (for parameters where a mean ELV applies) Overall Compliance (Pass/Fail) Pass Pass Pass Fail Pass Pass Blessington WWTP is not designed to remove nitrogen. Significance of results The WWTP was compliant with the ELVs set in the wastewater discharge licence, with the exception of Ammonia, which was consistently breached. These breaches were due to the treatment plant not being designed to remove nitrogen. The impact on receiving waters is assessed further in Section 2.3. Page 3 of 23

6 2.3 Ambient monitoring summary Table Ambient Monitoring Report Summary Ambient Receiving Waters Designation (Y/N) WFD Status Does assessment of the ambient Monitoring Bathing Drinking FWPM Shellfish monitoring results indicate that the EPA Feature Point from Irish Grid Water Water discharge is impacting on water quality? Coding Tool WWDL (or as Reference code agreed with EPA) Upstream monitoring point Downstream monitoring point E N E N RS09L n/a n/a n/a n/a Moderate n/a RS09L N N N N Moderate Yes The results for the Ambient Monitoring are included as in Appendix 7.2. Significance of results The WWTP was non-compliant with the ELV s set in the wastewater discharge licence as detailed in Section 2.2. The discharge from the wastewater treatment plant does have an observable negative impact on the water quality in terms of Ammonia based on the 2015 ambient monitoring results. The discharge from the wastewater treatment is likely to be having an observable negative impact on the Water Framework Directive status in terms of ammonia. It is noted that consistent achievement with the ELVs would benefit the quality of the receiving water and its WFD status. 2.4 Data collection and reporting requirements under the Urban Waste Water Treatment Directive The reporting requirement under the Urban Wastewater Directive is completed by electronic submission of data was completed on 25/02/ Pollutant Release and Transfer Register (PRTR) - report for previous year The PRTR is not required for the 2015 AER. 4 Irish Water

7 Section 3 Operational Reports Summary 3.1 Treatment Efficiency Report A summary presentation of the efficiency of the treatment process including information for all the parameters specified in the licence is included below:- Table Treatment Efficiency Report Summary cbod COD (kg/yr) (kg/yr) Influent mass loading (kg/year) Effluent mass emission (kg/year) % Efficiency (% reduction of influent load) SS (kg/yr) Total P (kg/yr) Total N (kg/yr) 126, , ,148 3,266 23,146 2,948 18,016 4, ,803 98% 94% 97% 93% 45% Comment 3.2 Treatment Capacity Report Table Treatment Capacity Report Summary Hydraulic Capacity Design / As Constructed (dry weather flow) (m 3 /year) 492,750 Hydraulic Capacity Design / As Constructed (peak flow) (m 3 /year) 1,478,250 Hydraulic Capacity Current loading (m 3 /year) 333,030 Hydraulic Capacity Remaining (m 3 /year) 1,145,220 Organic Capacity - Design / As Constructed (PE) 6,000 Organic Capacity - Current loading (PE) 5,790 Organic Capacity Remaining (PE) 210 Will the capacity be exceeded in the next three years? (Yes / ) 3.3 Extent of Agglomeration Summary Report In this section Irish Water is required to report on the amount of urban waste water generated within the agglomeration. It does not include any waste water collected and treated in a private system and discharged to water under a Section 4 Licence issued under the Water Pollution Acts 1977 (as amended): 5 Irish Water

8 Table Extent of Agglomeration Summary Report % of p.e. load generated in the agglomeration Load generated in the agglomeration that is collected in the sewer network 100% Load collected in the agglomeration that enters treatment plant 100% Load collected in the sewer network but discharged without treatment 0% Load generated in the agglomeration that is collected in the sewer network is the total load generated and collected in the municipal network within the boundary of the agglomeration. Load collected in the agglomerations that enters treatment plant is that portion of the previous figure which enters the waste water treatment plant Load collected but discharged without treatment is that portion of the first figure which is discharged without treatment. Table 3.3 above is based on overflow data. 3.4 Complaints Summary A summary of complaints of an environmental nature is included below. Table Complaints Summary Table: Number Date & Time Nature of Complaint /02/2015 Reported sewage 13:59 near Blessington Lake /02/ :08 Blocked drain overflowing Cause of Complaint Malfunction with the Knockieran wwtp (A0014). This is NOT in the D0063 agglomeration. Actions taken to resolve issue Repairs carried out to the treatment plant Blocked sewer Sewer jetting Y Closed (Y/N) Y /01/ : /04/ : /06/ : /05/ : /07/ : /09/ : /10/ :56 Blocked sewer main Blocked sewer Sewer jetting Y Blocked sewer main Blocked sewer Sewer jetting Y Blocked sewer main Blocked sewer Sewer jetting Y Blocked sewer main Blocked sewer Sewer jetting Y Blocked sewer main Blocked sewer Sewer jetting Y Blocked sewer main Blocked sewer Sewer jetting Y Blocked sewer main Blocked sewer Sewer jetting Y 6 Irish Water

9 3.5 Reported Incidents Summary A summary of reported incidents is included below. Table Summary of Incidents Incident Type (e.g. ncompliance, Emission, spillage, Emergency Overflow Activation) Breach of ELV Incident Description Breach of ammonia ELV Cause The treatment plant is not designed to remove nitrogen.. of incidents 12 (monthly report) Corrective Action Authorities Contacted te 1 Reported to EPA (Yes/) ne IFI Y N Closed (Y/N) Uncontrolled Release of treated wastewater to ground (a storm storage lagoon) Uncontrolled Release commenced 12/08/15 The primary discharge is pumped to the receiving water. The rising main burst. 1 Rising main repaired IFI Y Y te 1: For shellfish waters notify the Marine Institute (MI) Sea Fisheries Protection Authority (SFPA) Food Safety Authority (FSAI) and An Bord Iascaigh Mhara (BIM). This should also include any other authorities that should be contacted arising from the findings of any Licence Specific Reports also e.g. Drinking Water Abstraction Impact Risk Assessment, Fresh Water Pearl Mussel Impact Assessments etc. Table Summary of Overall Incidents Number of Incidents in Number of Incidents reported to the EPA via EDEN in Explanation of any discrepancies between the two numbers above discrepancy NOTE ON REPORTING AMMONIA EXCEEDENCES: All Ammonia monitoring results (including process monitoring) are notified monthly to the Agency via EDEN as an action required arising from Compliance Investigation CI Irish Water

10 3.6 Sludge / Other inputs to the WWTP Other inputs to the waste water treatment plant are summarised in Table 3.6 below. Table Other Inputs 1,2 Input type m 3 /year PE/year % of load to WWTP Domestic /Septic Tank Sludge Included in Influent Monitoring (Y/N)? 3 Is there a leachate/sludge acceptance procedure for the WWTP? (Y/N) N N N Is there a dedicated leachate/sludge acceptance facility for the WWTP? (Y/N) Industrial / Commercial Sludge Landfill Leachate (delivered by tanker) Landfill Leachate (delivered by sewer network) Other (sludge from nearby small municipal treatment plants ) N N N N N N N N N 577 m Y Y Y tes: 1. Other Inputs include; septic tank sludge, industrial /commercial sludge, landfill leachate and any other sludge that is collected and added to the treatment plant. 2. Sludge that is added to a dedicated sludge reception facility at a waste water treatment plant not included in Table 3.6. Only include sludge which is added to the waste water treatment process stream. Enter zero where there are no inputs. 3. If any inputs were introduced prior to influent monitoring point and therefore already reported in S.2.1 Influent Monitoring Summary, then clarify this to avoid duplication and over-reporting of PE. 8 Irish Water

11 Section 4. Infrastructural Assessments and Programme of Improvements 4.1 Storm water overflow identification and inspection report There are no storm water overflows. Table SWO Identification and Inspection Summary Report Irish Grid Ref. WWDL Name / Code for Storm Water Overflow There are no storm water overflows There are no storm water overflows Included in Schedule A4 of the WWDL There are no storm water overflows Significance of the overflow (High / Medium / Low) Compliance with DoEHLG Criteria. of times activated in 2015 (. of events) Total volume discharged in 2015 (m 3 ) Total volume discharged in 2015 (P.E.) Estimated /Measured data Table SWO Identification and Inspection Summary Report How much sewage was discharged via SWOs in the agglomeration in the year (m 3 /yr)? How much sewage was discharged via SWOs in the agglomeration in the year (p.e.)? What % of the total volume of sewage generated in the agglomeration was discharged via SWOs in the agglomeration in 2015? Is each SWO identified as non-compliant with DoEHLG Guidance included in the Programme of Improvements? The SWO assessment includes the requirements of Schedule A3 & C3 Have the EPA been advised of any additional SWOs / changes to Schedule C3 and A4 under Condition 1.7? N/A N/A N/A N/A N/A N/A 4.2 Report on progress made and proposals being developed to meet the improvement programme requirements. The Improvement Programme is included in Appendix 7.3. Table addresses the Specified Improvement Programmes in respect of Schedules A3 and C of the WWDL. 9 Irish Water

12 Table Specified Improvement Programme Summary Specified Improvement Programmes (under Schedule A and C of WWDL) There are no Improvements specified in the Licence Licence Schedule (A or C) Licence Completion Date Date Expired? (N/NA/Y) ne ne N/A There are no works. Status of Works ((i) t Started; (ii) At planning stage; % (iii) Work Construction ongoing onsite; (iv) Work Completed Commissioning Phase; (v) Completed; (vi) Delayed) Timeframe for Completing the Work N/A N/A N/A Comments A summary of the status of any improvements identified by under Condition 5.2 is included below. Table Improvement Programme Summary Improvement Identifier Improvement Description Improvement Source Progress (% completed) Expected Completion Date Assessment of the effectiveness of the treatment having regard to the Emission Limit Values specified in Schedule A: Discharges of the Licence. Assessment on the feasibility study of technologies and proposals regarding interim ammonia reduction A process optimisation review was completed on-site in October Having assessed processes optimisation recommendations, IW hope to optimise and enhance nitrification by supplementing alkalinity in the system on a trial bases During this period operational monitoring will be undertaken to assess ammonia EPA Compliance Investigation CI % The targeted date for commencement of this trial is Q Timeframes for key miles-stones in relation to the alkalinity trial are not currently available, as this trial is only scheduled to commence this quarter. 10 Irish Water

13 Improvement Identifier Improvement Description Improvement Source Progress (% completed) Expected Completion Date Assessment of Blessington WwTP reduction and overall compliance with ELV s. Consultants were appointed in May 2015 to carry out an assessment of Blessington WwTP. EPA Compliance Investigation CI % This assessment is progressing on track and the report is due to be submitted to Irish Water at the end of Q Structural Risk Assessment A CCTV sewer condition survey and assessment is required to develop performance criteria, and to determine sewer conditions Sewer Integrity Tool (Condition 5.2) 0% Unknown Improvements identified above also include measures taken to prevent environmental damage anticipated following events or accidents/incidents associated with discharges or overflows from the waste water works and as such are considered to fulfil any Statement of Measures requirements. Table Sewer Integrity Risk Assessment Tool Summary The Improvement Programme should Risk Assessment include an assessment of the integrity of the Rating (High, existing wastewater works for the following: Medium, Low) Hydraulic Risk Assessment Score Environmental Risk Assessment Score Structural Risk Assessment Score Operation & Maintenance Risk Assessment Score Overall Risk Score for the agglomeration LOW RISK 34% Risk Assessment Score Comment MEDIUM RISK 48% Appendix F in the 2012 AER LOW RISK 19% Appendix F in the 2012 AER HIGH RISK 100% Appendix F in the 2012 AER LOW RISK 10% Appendix F in the 2012 AER 11 Irish Water

14 Section 5. Licence Specific Reports Licence Specific Reports Summary Table Required in AER or Licence Specific Report outstanding from previous AER Priority Substances Assessment Report Included in AER Reference to relevant section of AER (e.g. Appendix 2 Section 4). Monitoring results were included in the 2012 AER priority substances were identified. Drinking Water Abstraction Point Risk Assessment Habitats Impact Assessment Shellfish Impact Assessment Pearl Mussel Report Toxicity/Leachate Management Toxicity of Final Effluent Report Licence Specific Reports Summary of Findings Licence Specific Recommendations Report in Report Summary of Recommendations in Report Priority Substances Assessment ne t applicable Drinking Water Abstraction Point ne t applicable Risk Assessment Habitats Impact Assessment ne t applicable Shellfish Impact Assessment ne t applicable Pearl Mussel Report ne t applicable Toxicity/Leachate Management Toxicity of Final Effluent Report ne ne t applicable t applicable 12 Irish Water

15 5.1 Priority Substances Assessment The Priority Substances Assessment report was included as an Appendix in the 2012 AER. priority substances were identified. Table Priority Substance Assessment Summary Does the assessment use the Desk Top Study Method or Screening Analysis to determine if the discharge contains the parameters in Appendix 1 of the EPA guidance Does the assessment include a review of Trade inputs to the works? Does the assessment include a review of other inputs to the works? Does the report include an assessment of the significance of the results where a listed material is present in the discharge? (e.g. impact on the relevant EQS standard for the receiving water) Does the assessment identify that priority substances may be impacting the receiving water? Does the Improvement Programme for the agglomeration include the elimination / reduction of all priority substances identified as having an impact on receiving water quality? Licensee self- assessment checks to determine whether all relevant information is included in the Assessment. Desk Top Study and Screening Analysis Yes Yes listed material is present in the discharge in quantities likely to cause impact elimination/reduction required 5.2 Drinking Water Abstraction Point Risk Assessment. Assessment required by the Licence. 5.3 Shellfish Impact Assessment Report. Assessment required by the Licence. 5.4 Toxicity / Leachate Management Assessment required by the Licence. 5.5 Toxicity of the Final Effluent Report Assessment required by the Licence. 5.6 Pearl Mussel Measures Report Assessment required by the Licence. 5.7 Habitats Impact Assessment Report Assessment required by the Licence. 13 Irish Water

16 Section 6. Certification and Sign Off Table Summary of AER Contents Does the AER include an Executive Summary? Does the AER include an assessment of the performance of the Waste Water Works (i.e. have the results of assessments been interpreted against WWDL requirements and or Environmental Quality Standards)? Is there a need to advise the EPA for consideration of a Technical Amendment / Review of the licence? List reason e.g. additional SWO identified (insert lines as required) Is there a need to request/advise the EPA of any modifications to the existing WWDL? Refer to Condition 1.7 (changes to works/discharges) & Condition 4 (changes to monitoring location, frequency etc.) List reason e.g. failure to complete specified works within dates specified in the licence, changes to monitoring requirements (insert lines as required) Have these processes commenced? (i.e. Request for Technical Amendment / Licence Review / Change Request) Are all outstanding reports and assessments from previous AERs included as an appendix to this AER? List outstanding reports (insert lines as required) Yes Yes t applicable t applicable t applicable ne outstanding ne Declaration by Irish Water The AER contains the following; Introduction and background to AER Monitoring reports summary. Operational reports summary. Infrastructural Assessment and Programme of Improvements. Licence specific reports. Certification and Sign Off Appendices I certify that the information given in this Annual Environmental Report is truthful, accurate and complete: Signed: Date: 09/02/2016 Gerry Galvin Chief Technical Advisor 14 Irish Water

17 Section 7. Appendix Appendix 7.1 Annual Statement of Measures Appendix Ambient Monitoring Appendix 7.3 Specified Improvement Programme 15 Irish Water

18 APPENDIX 7.1 Annual Statement of Measures Improvements identified in Section 4 of the main AER document include measures taken to prevent environmental damage anticipated following events or accidents/incidents associated with discharges or overflows from the waste water works and as such are considered to fulfil any Statement of Measures requirements. additional measures have been taken in 2015 in relation to prevention of environmental damage. The need for measures to prevent of environmental damage will be reviewed on an annual basis. Refer also to Appendix Irish Water

19 APPENDIX 7.2 Ambient Monitoring SCHEDULE B.3 PARAMETERS Ambient monitoring results UPSTREAM (Station Pollaphuca Dam Wall) for the parameters as set out in Schedule B.3 Date ph DO BOD Total Phosphorus (mg/l-p) Ortho phosphate (mg/l-p) Total N (mg/l-n) Ammonia (mg/l-n) 20/01/ <1 <0.01 < /02/ <1 <0.01 < < /03/ <1 <0.01 < /04/ <1 <0.01 < < /05/ <1 <0.01 < /06/ <1 <0.01 < /07/ <1 <0.01 < /08/ <1 <0.01 < < /09/ <1 <0.01 < /10/ <1 <0.01 < /11/ < < *Mean *95%ile Mean EQS %ile EQS * EQS from Surface Water Objectives (S.I of 2009). Where the concentration in the result is less than the limit of detection (LOD), a value of 50% of the LOD was used in calculating the mean and 95%ile concentrations. Ambient monitoring results DOWNSTREAM (Station mid Golden Falls Lake sample) for the parameters as set out in Schedule B.3 Date ph DO BOD Total Phosphorus (mg/l-p) Ortho phosphate (mg/l-p) Total N (mg/l-n) Ammonia (mg/l-n) 20/01/ < < /02/ < < /03/ < < /04/ < < /05/ < /06/ < /07/ <1 < Irish Water

20 19/08/ <1 <0.01 < /09/ <1 <0.01 < /10/ <1 <0.01 < /11/ < < *Mean *95%ile Mean EQS %ile EQS * EQS from Surface Water Objectives (S.I of 2009). Where the concentration in the result is less than the limit of detection (LOD), a value of 50% of the LOD was used in calculating the mean and 95%ile concentrations. 18 Irish Water

21 APPENDIX 7.3 Programme of Improvements Assessment Condition 5.1 of the Licence requires a programme of infrastructural improvements to maximize the effectiveness and efficiency of the waste water works to be submitted in order to: (a) Achieve improvements in the quality of the discharge from the works. (b) Meet the Emission Limit Values Specified in Schedule A: Discharges, of the Licence. (c) Give effect to Regulation 2 of the Waste Water Discharge (Authorisation) Regulations 2007, as amended. (d) Reduce Total Phosphorus loadings in the discharge to the maximum practicable extent. (e) Meet the obligations of Condition 1.7 (which requires an assessment of the remaining treatment capacities and the maintenance of available capacities). 1. Assessment as required by Condition 5.2 (a) The programme of infrastructural improvements referred to in Condition 5.1 shall include an assessment of the waste water treatment plant, having regard to the effectiveness of the treatment provided by reference the various headings stated in the following Table: - CONDITION 5.2(a) HEADING (i) Assessment of the existing level of treatment, capacity of treatment plant and associated equipment. ASSESSMENT and IDENTIFICATION of any REQUIRED IMPROVEMENT Consultants were appointed in May 2015 to carry out an assessment of Blessington WwTP. TIMEFRAME for the IMPLEMENTATION of the IMPROVEMENT and the ELV AFFECTED as a result (if applicable) This assessment is progressing on track and the report is due to be submitted to Irish Water at the end of Q (ii) Assessment of the effectiveness of the treatment having regard to the Emission Limit Values specified in Schedule A: Discharges of the Licence. Assessment on the feasibility study of technologies and proposals A process optimisation review was completed on-site in October Having assessed processes optimisation recommendations, IW hope to optimise and enhance nitrification by supplementing alkalinity in the system on a trial bases During this period operational monitoring will be undertaken to assess ammonia reduction and overall compliance with ELV s. The targeted date for commencement of this trial is Q Timeframes for key milesstones in relation to the alkalinity trial are not currently available, as this trial is only scheduled to commence this quarter. 19 Irish Water

22 CONDITION 5.2(a) HEADING regarding interim ammonia reduction (iii) Assessment of the effectiveness of the treatment having regard to the designations of the receiving water body. ASSESSMENT and IDENTIFICATION of any REQUIRED IMPROVEMENT There are no designations (EQS, Pearl Mussel, Shellfish, SAC, SPA etc.) for the receiving waters. Improvement Works are required arising from any designation. TIMEFRAME for the IMPLEMENTATION of the IMPROVEMENT and the ELV AFFECTED as a result (if applicable) timeframe required. (iv) Assessment of the effectiveness of the treatment having regard to the downstream abstraction and uses of water. (v) Assessment of the effectiveness of the treatment having regard to the water quality objective(s) for the receiving water body. Any downstream abstraction point is remote from the discharge. Improvement Works are required. A process optimisation review was completed on-site in October Having assessed processes optimisation recommendations, IW hope to optimise and enhance nitrification by supplementing alkalinity in the system on a trial bases During this period operational monitoring will be undertaken to assess ammonia reduction and overall compliance with ELV s. timeframe required. The targeted date for commencement of this trial is Q Timeframes for key milesstones in relation to the alkalinity trial are not currently available, as this trial is only scheduled to commence this quarter. (vi) Assessment of the effectiveness of the treatment having regard to the standards and volumetric limitations applied to any industrial waste water that is licensed to discharge to the waste water works. A Priority Substances Assessment was carried out and was included in the 2012 AER. The conclusion is that the discharges do not give concern in respect of Priority Substances and that no improvement works are required in respect of discharges licenced by Section 16 of the Water Pollution Act. Improvement Works are required. timeframe required. 20 Irish Water

23 2. Assessment required by Condition 5.2 (b) This refers to an assessment of the integrity of the waste water works required under the following headings stated in Condition 5.2(b): - (i) Capacity of the waste water works (ii) Leaks from the waste water works (iii) Misconnections between foul sewers and surface water drainage network (iv) Infiltration by surface water (v) Infiltration by groundwater (vi) Such other works as may be specified by the Agency An assessment of the above was carried out using the EPA s tool Assessment of the Integrity of Sewers and their Accessories (Rev B June 2012). The Assessment is available as an Appendix in the 2012 AER. The results are repeated in the Table below: Sewer Integrity Risk Assessment Heading Risk Assessment rating Improvement Identified Implementation Hydraulic Risk Assessment Score MEDIUM RISK Hydraulic Performance assessments and Dynamic Modelling of the collection system are required. Timeframe determined. Environmental Risk Assessment Score LOW RISK improvement identified. implementation required Structural Risk Assessment HIGH RISK A CCTV sewer condition survey and assessment is required to develop performance criteria, and to determine sewer conditions. Timeframe determined. Operation & Maintenance Score LOW RISK Blockages, which give rise to overflows from the collection system, need to be recorded. Blockages are recorded. Timeframe required. 21 Irish Water