NON TECHNICAL SUMMARY

Transcription

1 NON TECHNCAL SUMMARY Louth County Council, County Hall, Millennium Centre, Dundalk, Co. Louth is making an application to the Environmental Protection Agency (EPA) for a Waste Water Discharge Licence, for Dundalk Waste Water Treatment Plant & Agglomeration, in compliance with the Waste Water Discharge (Authorisation) Regulations 2007 (S.. No. 684 of 2007). Under Schedule 2 of the above regulations, the prescribed date for submission of Waste Water Discharge Licence Applications for agglomerations (with discharges with a population equivalent of more than 10,000PE) is 14 December The waste water works at Dundalk falls under this category, prently having an agglomeration with a population equivalent of 179,107PE. The agglomeration rves: Dundalk Town, in the administrative area of Dundalk Town Council; and the northwestern, western and southwestern environs of Dundalk (bounded to the west by the M motorway) in the administrative area of Louth County Council. The agglomeration extents are clearly shown on Figure 1 attached. The agglomeration is rved by the Dundalk Wastewater Treatment Plant (WWTP), Soldiers Point, Point Road, Dundalk. The WWTP location is shown on Figure 1 attached. Dundalk WWTP is a two-stage Secondary Treatment Plant, consisting of an initial high load aeration stage, with intermediate clarification, followed by a low-load aeration stage and Final Clarification. t has been designed, by appropriate space provision for future tankage and anoxic zones, to accommodate future Nitrogen removal. The WWTP site plan and process flow diagram are shown on Figure 2 and Figure 3 attached. 'EPS Pumping & Treatment Systems' are the 'Operational & Maintenance Contractors' for the WWTP & associated pump stations. The WWTP is supervidlmanned from 8.30am to 5.00pm Monday to Friday. An onsite laboratory, with a full-time chemist also operates during the hours. The treated effluent from the WWTP discharges through an outfall pipe to the Castletown River Estuary (Soldiers Point, Point Road, Dundalk), as shown on Figure 4. This is the Primary Discharge Point from the waste water works. t discharges continuously, at a designed DWF of 18,902m3/day. The Castletown Estuary is part of Dundalk Bay Special Area of Conrvation (SAC), Natural Heritage Area (NHA) and Special Protected Area ) (SPA). However, as the effluent being discharged from the Primary Discharge Point is fully treated within the WWTP (prior to discharge), it is not expected to have a significant effect on the Dundalk Bay SAC, NHA & SPA. t is not possible to monitor locations upstream and downstream of the Primary Discharge Point, as the discharge point (Castletown River Estuary) is tidal, and thus flow directions, etc. are constantly changing. o ow ever, the EPA continues to carry out much rearch in this area, as part of their 'Water Framework Directive' obligations. Full records of this sampling, etc., are available from the EPA. The Waste Water Works has three condary discharge points (SEC-1, SEC-2 & SEC- 3), which are emergency overflows from the St. Helena, the Boyle O'Reiliy and the Coes Road Pumping Stations. They will only operate in the exceptional ca of complete pump failure at the pumping station. There is no history of this occurring, nor is it expected in the future. The plants are designed to hold ten times the DWF of their catchments and have a stand by generator to run the pumps in ca of an electricity failure. Therefore, bad on the above, it is not expected that emissions from the condary discharges could have a significant effect on the receiving waters. SEC- discharges to the Boyne Estuary, which is within the Dundalk Bay SAC & SPA. SEC-2 &

2 SEC-3 discharge to waters (Castletown River Estuary & Blackewater River) that have no designation. Also, bad on the above, it is not possible to monitor the discharge at the locations, or upstreamldownstream of the discharge points. The three condary discharge points are shown on Figure 4 attached The Dundalk Waste Water Works includes a total of 9 no. Storm Water Overflows, named SWO-1 - SWO-9. All discharge locations are shown on Figure 4 attached. The Storm Water Overflow SWO-1 (storm water overflow from the WWTP storm holding tanks at the WWTP) discharges to the Castletown River Estuary, which is within Dundalk Bay SAC, NHA and SPA. SWO-1 will only relea effluent to the riverlbay once the volume of the stormwater tanks is exceeded. Therefore, ongoing monitoring and sampling at this discharge point is not possible. Should the effluent from the storm tanks be relead, it is expected to be diluted to such a degree that it is not expected to have a significant effect on Dundalk Bay SACNHASPA. Discharge of effluent from Storm Water Ovefflows (SWO-2 - SWO-9) from the eight pumping stations within the catchment, will only occur in times of very heavy precipitation (when quantities are > 6 times the DWF in the catchment). Should the effluent be 1 relead, it is expected to be diluted to such a degree that it is not expected to have a significant effect on the receiving environment. SWO-2, SWO-3 & SWO-8 discharge to the Castletown River Estuary (within Dundalk Bay SACSPA). SWO-4, SWO-5, SWO-6, SWO-7 & SWO-9 all discharge to waters that have no designation. As part of the planning process for the 'Dundalk Waste Water Treatment Works', in 1994, an ES was produced. A copy of this ES is attached to the prent Licence application. This document discuss in detail the design for the Waste Water Works and investigates the possible impacts the works and their discharges could have on the surrounding environment. t also discuss the Mitigation Measures to be put in place, in order to avoid any negative impacts from the waste water works on the surrounding environment. t is propod to continue monitoring the treated effluent from the Primary Discharge Point from the Dundalk WWTP on a dailylweekly basis, in order to ensure good standards of effluent quality are being achieved.

3 . ru he ot f c Fo op r i yr ns ig pe ht ct ow ion ne pu r r rp eq os ui es re o d nl fo y. ra ny nt o Co n AGGLOMERATE EXTENT 8 BOUNDARY SHOWNG LOCAL AUTHORTY AREAS 8 WWTP LOCATON (, WM-TECHNCALSUMMAW,,) Srnb@*l 1 : Pnpaildq; Chocked o*c RK ES DEC '07 PmleaOn*r MCHAEL F. GARRCK

4 WWTP SlTE BOUNDARY PRMARY DSCHARGE 3. ENOlNEERTO BE NFORMS0 BY THE CONTRACTOR OF&NDSCREPhNCES BEFORE ANY WORKCOMMENCES (.ALL LEVELS SHOWN REMTETOORONWE SURYEOTUMATMAUN HEAD LOUTH COUNTY COUNCL. Pmw: DUNDALK WASTE WATER DSCHARGE LCENCE APPLCATON PLANT PROCESS SlTE PLAN R.K. E.S. DEC ll7 Pio(ocf Oir- MCHAEL F. GARRCK

5 A OUTFALLTO CASTLETOWN RVER ESTUARY STORMWATER HOLDNG TANK ( 4 CELLS ) CASCADE CHAMBER A FNAL EFFLUENT SAMPLNG 3 NO. FRST STAGE 3 NO. SECOND STAGE CLARFERS PROCESS WATER P JMP NG STAT ON SECOND STAGE AERATON BASN WASHED SREENNGS 8 GRT FOR OFF-STE DSPOSAL EXTERNAL SLUDGES FOR SLUDGE THCkEhlNG. DGESTiOh. DEWATERNG TREATMENT WORKS STE PUMPNG STATON PUMPNG STATON TREATED SLLDGE FOR OFF-STE DSPOSAL FGURED DMENSONS ONLY TO BE TAKEN FROM is DRAWNG A-- DRAW NGS TO BE ChECkED BY TrlE OhTRACTOR Oh S TE ENGNEER TO BE NFORMED BY THE CONTRACTOR F ANY DSCREPANCES BEFORE ANY WORK 3MMENCES ALL LEVELS SHOWN RELATE TO ORDNANCE SURVEY 4TUM AT MALN HEAD C"en':LOUTH COUNTY COUNCL Prepared by: e TOBN Consulting Engineen. R.K. 3+- TOBlN Market Square. Casllebar, Co. Mayo. reland. Pmject: Checked: tel: +353-(0) DUNDALK WASTE WATER MFG Pairick J. ~obin 8 CD. LM fax:+353i0) Date: casuebar@tobin.ie my uu of N, docvmmt fw my pv- dh. l!m lhol fw Mch l rol dplndy -md end palkd. Title: Pmjecl Director: ziz cw - -d US. davmnt -11 not ~ n~.d "pa 22% 4 ow UM or Revision: DSCHARGE LCENCE APPLCATON DEc -0, WN -vl~q ~n wn WM not be BM i~ bmltt.d 1" '~$h~tr.~~rt%~/n~~m?n?p~ A SSUE TO EPA R.K PLANT PROCESS FLOW DAGRAM M. GARRCK fw.w P~V-. E.S. A3: Drawing No.: (NoN-TEcHNcAL SUMMARY) N.T.S. FGURE3 A Rev Date Description By Chkd. d

6 WWTP SlTE BOUNDARY SECONDARY DSCHARGE TOWN BOUNDARY STORM WATER OVERFLOW DSCHARGE PONT! 1350mm0 STORM OUTFALL SEWER. NOTES ot he ru.flgureo OMEN510N5 O N L T O BETAKEN FROMNE ORLWlNO f c Fo op r i yr ns ig pe ht ct ow ion ne pu r r rp eq os ui es re o d nl fo y. ra ny 2.kLL -WNGS TDBE CHECKED BY THE CMTRACTOR ON STS 3 ENOlNEERTO BE NFORMED B T H E CONTRACTOR OF ANDSCREPWCES BEFORE ANY WDRKCOMMENCES Co n nt o 1. ALL LEVELS SHOWN RELATETOORONlWCE SURVEY D A N M A T M A W HEAD Climt LOUTH COUNTY COUNCL PmW: DUNDALK WASTE WATER DSCHARGE LCENCE APPLCATON Tds: WWTP LOCATON 8 SlTE BOUNDARY 1 NCLUDNG DSCHARGE. MONTORNG &SAMPLNG PONTS ) Pmwred b Ch*Cld. P m W Diraol: MCHAEL F. GARRCK DEC '07 ordnance Survey lrsland Licsns~No EN WlW07 OOrdnance Svrvsy reland and Government of lrsland