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This document has been cleared for submission to the Board by the Senior Inspector, Dr Karen Creed a Signed: ~.-~f~;~~~7~Date: iH5- LPll\r>ll\W cu l\fic9uul\bm VU&. INSPECTORS REPORT ON A WASTE WATER DISCHARGE LICENCE APPLICATION Directors 11 From: Aoife Loughnane Environmental Licensing Programme 11 Date: 14th September 2012 Application for a Waste Water Discharge Licence from Donegal RE: 1 County Council for the Lifford agglomeration, Reg. No. D0352-01. SEhedule ad blscharge ritad: 'Discharges from agglomerations with a population equivalent of 1,001 to 2,000. L)cemapplkatfon rwdved: 12/06/2009 Mbtlaes under flqulatlstll8(3)(b] issued: 21/09/2010, 26/06/2012 Inbrmatlon under Regulation it3[3)[b) 14/07/2011, 3/07/2012 redwed: We mthdwxk; 26/06/2009 5ik vlsit: 22/07/2010 (Anne Pearson, OCLR) submlssbm ml&: Ten: I > Mr. P.E. Lusby 19/02/2010, 25/05/2012, 30/08/2012, 5/09/20 12, 10/09/2012 & 13/09/2012 > Mr. Mark McGavigan 10/02/2012 > NPWS 9/07/2012 > Loughs Agency 11/07/2012 > NIEA 10/9/2012 1. Agglomeration This application relates to the Lifford agglomeration in eastern Donegal. Lifford is located on the west bank of the River Foyle, across the river from Strabane, Co. Tyrone. The two border towns are linked by the Lifford Bridge. Approximately 250m upstream of Lifford Bridge, the River Foyle is formed at the confluence of the River Finn which drains large areas of Donegal, and River Mourne which drains large areas of Northern Ireland. The River Foyle becomes the Foyle estuary (tidal/transitional waters) approximately 50m downstream of Lifford Bridge (see map in Appendix A). The Foyle estuary enters Lough Foyle coastal waters 30km north-east of Lifford. Donegal County Council has identified the existing population equivalent (p.e.) of the Lifford agglomeration as 1,969. Growth to 2,041 p.e. is projected based on planning permissions granted for developments yet to commence. A revised licence may be required should the p.e. of the agglomeration exceed 2,000. The breakdown in contribution is approximately 74% domestic, 14% commercial, 10% institutional and 2% leisure/tourism. There are no identified sources of industrial waste water in Lifford. Page 1 of 17 I The waste water collection network is predominantly a combined system. Most of the network dates from the 1960s, with extensions along the N15 Stranorlar Road and the N14 Letterkenny Road. There is one pumping station and two storm water overflows on the collection network. Lifford’s waste water currently undergoes primary treatment in a 125m3 septic tank, prior to discharging to the Foyle estuary. The septic tank is located east of the town and was installed in 1967 to serve a population of 1,550. It has not received any major refurbishment since. There is a coarse bar screen on the inlet to the tank. Because the plant is overloaded, it provides limited treatment of waste water. The tank is desludged occasionally by a mobile dewatering unit, and the sludge is transported for treatment to the sludge hub at Donegal Town. The Lifford agglomeration is below the 2,000 p.e. threshold for discharges to estuaries, at which the emission limit values specified in the Urban Waste Water Treatment Regulations apply (25: 125:35 mg/l for B0D:COD:SS respectively). For agglomerations below this threshold, ‘appropriate treatment’ was required by 3lSt December 2005, as specified in Article 7 of the Regulations. The term ‘appropriate treatment’ is defined in the Regulations as ‘treatment of urban waste water by any process and/or dispod system which after discharge allows the receiving waters to meet the relevant quality objectives and the relevant provisions of the Directive and of other Community Directives!. The existing septic tank in Lifford provides primary treatment and is significantly overloaded (1,550 p.e. capacity compared to a current loading of 1,969 p.e.). The current level of treatment is not considered appropriate treatment. A new WWTP is required to provide, as a minimum, secondary treatment. Lifford sewerage scheme is not listed on the Water Services Investment Programme (WSIP) 2010-2012. Donegal County Council has acknowledged that secondary treatment is required in order to meet National and European legislation. The preliminary report on the upgrade needs has not yet been prepared. Donegal County Council has identified a number of specific issues in the licence application, including:- inadequate treatment and capacity at the existing WWTP, inadequate capacity and condition of sewers, flooding at the pumping station during wet weather when pumps and rising mains are unable to cope with the inflow, and 0 storm overflows that frequently discharge unscreened waste water. The Foyle estuary is classified as ‘moderate’ status under the Water Framework Directive. The objective is to restore to ’good’ status by 2021. In the North Western IRBD Transitional and Coastal Waters Action Plan, the Foyle estuary is identified as “at risk” or “probably at risk” from point source pressures - WWTPs, combined sewer overflows and treatment plant overflows. The Rnn/Derg/Foyle Water Management Unit Action Plan identifies Lifford WWTP as a point pressure and “at risk due to future insufficient WWTP capacity”. The measures/capital works set out in the plan are to increase the capacity of Lifford WWTP. The timeframe is identified as 2015+. I have consulted with the DoECLG Inspector for waste water services in Donegal regarding the upgrade of Lifford sewerage scheme. He has confirmed that the preparation of the preliminary report on the upgrade needs is due to commence in the near future, and he outlined the timelines involved in the preparation and approval of the preliminary report and contract documents, the tendering process and construction works. He has identified that 2017 is a realistic timeframe for completion of the sewerage scheme upgrade. Page 2 of 17 Having regard to the fact that Lifford sewerage scheme is not listed on the current WSIP, the preliminary report on the upgrade needs has not yet commenced and the Foyle estuary has an extended deadline until 2021 to be restored to good status, the Recommended Licence (RL) requires secondary waste water treatment to be provided in Lifford by 31‘ December 2017. The legislation under which the discharges from the waste water works are to be licensed does not provide any regulatory powers with regard to odour, noise or management of the waste water works infrastructure. Therefore, the RL does not specifically refer to, or set operating conditions, in relation to these areas. 2. Discharges to waters Primaty Discharqe The primary discharge (SWOOl) is the outfall from the septic tank to the Foyle estuary. The discharge point is located approximately 450m downstream of Lifford Bridge. As the primary discharge is into transitional waters, it is not possible to accurately measure the flow in the receiving water due to tidal variation. However, a conservative estimate of flow can be determined using the 95%ile flow in the River Foyle at Lifford Bridge, which is 7.98 m3/sec (provided by the Agency’s Office of Environmental Assessment Hydro Tool model). The normal flow rate of Lifford’s waste water discharge is 443 m3/day (0.0051 m3/sec). These flow rates indicate there are significant dilutions available in the receiving water, in the order of 1,564 dilutions of the waste water discharge at 95Ohile river flow. Tidal influences add further to the dilution capacity. The primary discharge is routinely grab sampled by Donegal County Council under their urban waste water monitoring programme. The average levels of BOD, COD and suspended solids are shown in Table 1, based on six samples per year. Table 1: Lifford waste water monitoring results, 2008 - 2009 The WWTP provides primary treatment, however because the plant is overloaded it provides limited treatment and the monitoring results indicate there is little or no effective treatment of waste water in the septic tank. Settlement of some solids, grit and heavier materials is all that is being achieved. The RL requires secondary waste water treatment to be provided in Lifford by 31st December 2017. Schedue A of the RL specifies emission limit values (ELVs) for the primary discharge from a new/upgraded WWTP, which will apply from 31St December 2017 (25 mg/l cBOD, 125 mg/l COD, 25 mg/l Suspended Solids, 10 mg/l Ammonia and 5 mg/l Ortho-phosphate). These ELVs are set with the aim of restoring good status in the Foyle estuary by 2021. In the meantime, Schedue A of the RL sets interim ELVs (primary treatment Oh reduction standards in accordance with the UWWT Directive) on the primary discharge, although these ELVs may be difficult to achieve given the infrastructure that is currently in place. Condition 3.4 of the RL requires the licensee to take such measures as are necessary to ensure that no deterioration occurs in receiving water quality as a result of the discharge. Page 3 of 17 I Secondary Discharges There are no secondary waste water discharges from the agglomeration. Storm Water OverRows (SWOs) There are two identified SWOs on the collection network, one at Hart's Bar, Bridge Street (SW002) and one at Lifford Roundabout (SW003), which both discharge at the same location into the River Foyle, just upstream of Lifford Bridge. Donegal County Council has stated that neither SWO complies with the DoECLG criteria and it is not known at this time whether they will be decommissioned as part of the sewerage scheme upgrade works. The RL requires the SWOs either to cease or be upgraded to comply with DoECLG criteria by 31' December 2017. Emergency OverROws (EOs) Table 2.