1 None. c----- Y. Dr Thomas McLoughlin REPORT ON A WASTE WATER DISCHARGE CE APPLICATION. To: DIRECTORS..

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1 This report has been cleared for Submission totheboard y DrKa Creed Signed: c----- Y Y - I I I L I 1 Y, LICENSING & RESOURCE USE. CTOI CE APPLICATION REPORT ON A WASTE WATER DISCHARGE - To: From: Date:.- DIRECTORS.. Dr Thomas McLoughlin 15* October 2009 E nvi ronmenta I Programme Licensing RE: Application for a Waste Water Discharge licence from Mayo County Council, for the agglomeration named Achill Island Central WWTP, Kcg. NO. D Application Details I! UIQUI iai ywu i I VI I I uyyiwi I 1-1 auui IU with a population equivalent of more than 2001 to 10,000 pe Licence application received: 18th September 2008 Notices under Regulation 18(3)(b) issued: 29' May 2009 Information under Regulation 18(3)(b) 13th July 2009 received: Site notice check: 16" October 2008 Site visit: 16' February 2009 Submission(s) Received: 1 None I - Agglomeration This application relates to the Achill Island Central agglomeration, which caters for the villages of Dooagh, Pollagh, Keel, Cabin, River and Dookenilla in Achill Island. The Wastewater Treatment Plant (WWTP) at Purtaen is situated in closc proximity to the Atlantic Ocean. It has a design capacity of 4,000 pe and has been operated by Mayo County Council since Treated effluent from the WW'l'P is discharged to the Atlantic Ocean (Primary Discharge Point.) at Purteen (See attached map-appendix 1). The waste water works consists of a WWTP with a collection network of foul sewers and four (4) pumping stations. The municipal treatment works is based on the extended aeration process and treats sewage from a population equivalent of 2500 pe which takes into account both residents and visitors who come to the island during the

2 peak summer holiday season. The municipal treatment process consists of the Iollowing : > Met works with 12mm automdtic screen, standby manual screen, screenings Bushed to macerator, compaction and grit removal > 2 No. Aeration Tanks P 2 No. Semndary Settling Tanks > Final Effluent Sampling Point P Sludge Pumping P Sludgc 'Thickening > Sludge Dewatering P Supernatant return to inlct works 2. Discharges to waters Primary Discharge Emissions from the WWTP are discharged via rocky shoreline through a primary discharge point SW 1 to the Atlantic Ocean at Purteen. The average discharge volume is given as 562.5m3/day, cquivalent to an average discharge of 162kg BODlday. Emergency Overflows There are three (3) emergency overflows, labelled SW2, SW3 and SW4. These emergency overflows are provided in case of difficulties, such as power cuts or pump failure, it should be noted that the infrastructure that is in place provides a high degree of protection for both Keel and Dooagh strands. Storm Water Overflows There is one storm water overflow (SW5) which shares the same outfall as the Primary Discharge point which discharges at flows in excess of 3 DWF. Schedule A: Discharges of the RD specifies the Emission Limit Values (ELVs) lo which the discharges from the Achill Island Central agglomeration must conform. The ELVs are aimed at providing a high dcgree of protection to the receiving water body. Monitoring of the discharges will take place as per ScheduZe B: Monitoring. 3. Receiving waters and impact The following table summarises the main considerations in relation to the Atlantic Ocean downstream of the primary discharge. Table 1.0 Receivinq waters Characteristic Clasaritication Rccciving water Atlantic ocean name and type Resource use Commercial fishing Amenity value k Beaches Comment Waterbody:Atlantic Occan Purteen harbour is used to land fish catches including: herring, mackerel, shrimp, plaice, sole, pot fishing for lobster & crab. Two designated bathing 2

3 > Boating, P Seaangling waters at Keel and Kern Beach which have Blue flag beach status. Applicable Regulations. -~ UWWT Rathing Note 2 Not compliant for 2007 due to the low number of samples taken. Compliant with Rathing waters regukttions Designations Achill Head Special Area of Conservation, Inishgallon NHA, Keel Machairmenam Cliffs Special Area o Conservation (SAC) and proposed Natural Heritage Area (PNHA) CroaghaunlSlievemore SAC and pnha (Site Code ). EPA monitoring stations No monitoring is carried out by the Agency in any of these designated sites with the exception of bathing watcr. WFD status WFD Risk Catagory WFT) protected areas... - Likely to be high Expected to achieve good status SAC S Keel and Ksem beaches Note 1 : Urban Waste Water Treatment Regulatims 2001 and 2M14 Note 2: Quality of Bathing Waters Regulations (S.I. IS5 of 1992) and Amendments According to the OEA, they advised that based on extrapolated data it is likely that the seas around Achill island would be at High status as there are very few inputs and a large open coastal influence. 4. Ambient Monitoring Ambient monitoring is already being carried out on both bathing water designated sites at Keel and Keem beaches during the batching season. Under Schedule B3, thcrc is a further requirement to carry out microbiological monitoring on a quarterly basis to to ensure that there is no deterioration in the status of the receiving water as a result of the discharge. Condition 4.17 requires the results and an interpretation of ambient monitoring to be reported as part of the AER. Where such results are available from the Agency or the Marine Institute, thcsc may be submitted in fulfilment of Schedule B3. 3

4 5. Programme of Improvements The WWTP in Achill Central, established in 1991, provides secondary treatment. There is no programme of improvements planned for the plant, or any of the infrastructure in the agglomeration. The conditions and emission limit values specificd in the RL should therefore emure no deterioration in the quality of the receiving waters as a result of the discharge. 6. Combined Approach The Waste Water Discharge Authorisation Regulations, 2007 (S.I. No. 684 of 2007) specify that a 'combined approach' in relation to licensing of waste water works must he taken, whereby the emission limits for the discharge are established on the basis of' the stricter of either or both, the limits and controls required under the Urban Waste Water Treatment Regulations (S.T. No. 254 of 2001) and the limits determined under statute or Directive for the purpose of achieving the environmental objcctives established for surface waters, groundwater or protected areas for the water body into which the discharge is made. The RL as drafted gives ei'fect to the principle of the Combined Approach as defined in S.I. No. 684 of Compliance with ELI DirectIves In considering the application, regard was had to the requirements of Regulation 6(2) of the Waste Water (Discharge) Authorisation, Regulations, 2007 (SI. No. 684 of 2007) notably: Water Framework Directive r2000/60/ec1 'lhc KL, as drafted, transposes the requirements of the Water Framework Directive. Tn particular, Condition 3 Discharges provides conditions regulating discharges to waters while Schedule A: Discharges specifies limit values for those substances contained within the waste water discharge. Those limits specified in the RL are determined with the aim of maintaining high status by 20 15, Urban Waste Water Treatment Directive C EEC1 Achill Island Central Agglomeration did not comply with the requirements of the Urban Waste Water Treatment Directive due to the low number of samples taken during The U, as drafted, has regard to the requirements of the Urban Waste Water 'I'reatment Directive. Bathing Water Directive 12006/7ECl Designated bathing watcrs located in the vicinity of the primary discharge are Keel and Keem beaches. In the Agency's report on 'The Quality of Bathing Waters in Ireland 2008 ', both bathing waters were deemed to comply with BU Mandatory and Guide Values (Good Quality) and National standards. Uangerous Substances Directive C2006/11/ECI The applicant has provided sampling results of the 19 dangerous substances in the primary discharge for the purposes of the licence application. The measured concentrations are not considered significant, Monitoring of receiving waters has shown compliance with the Dangerous Substances No. 12 of 2001). Furthermore, the RL requires scrsening of the primary discharge for the presence of organic compounds and metals within twelve months of the date of grant of licence. 4

5 Birds Directive [79/409/EEC1& Habitats Directive C921431EECI The WWTP at Purteen discharges into the Achill Head Special Area of Conservation, Keel MachairlMenaun Cliffi Special Area of Conservation (SAC) and proposed Natural Heritage Area (pnha) and Inishgallon NHA. In addition, the Croahun /Slievemore SAC and pnha arc located within 3km of the discharge points. Due to these Natura 2000 designations the Agency requested the applicant to provide evidence in relation to a determination as to the likelihood of discharges fiom the waste water works having a significant effect on these designated siks. An appropriate assessment was carried out by the Local Authority which concluded that the Achill Tsland Central WWTP and associated discharges are not having any significant impact on marine communities of naturc conservation value. Other Directives Condition 7.2 of the RL satisfies the requirements of the Environmental T.,iabilities Directive in particular those requirements outlined in Article 3(1) and Annex I1 of 2OM1351EC. Site Visit A sitc visit of the WWTP was carried out on 1 6th February The WWTP appeared to be operating satisfactorily. Submissions No submissions receivcd in relation to this application. C hsirges The RL sets an annual charge for the agglomeration at 2, and is reilective of the monitoring and enforcement regime being proposed for the agglomeration. Recommendation I recommend that a Find Licence be issued subject to the conditions and for the reasons as set out in the attached Recommended Licence. Signed Dr. Thomas McLoughlin Office of Climatc, Licensing and Resource Use 5

6 Appendix 1 : Map of Achill Island Central Agglomeration 6

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