Castletown Geoghegan Waste Water Treatment Plant Waste Water
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Castletown Geoghegan Waste Water Treatment Plant Waste Water Discharge Certificate of Authorisation Regulation 25(c)(ii) For inspection purposes Futher only. Information Consent of copyright owner required for any other use. Response (A0066-01) County Buildings Mullingar Co. Westmeath Phone: 04493 - 32000 Fax: 04493 -42330 Castletown Geoghegan WWDC 1 Appropriate Assessment Screening EPA Export 26-07-2013:19:22:55 Contents 1. Introduction 3 2. Revised Non-Technical Summary 3 3. Management of the Site 5 4. Project Description 5 4.1 Site Synpsos 6 4.1.1 Nure Bog NHA 6 4.1.2 Lough Ennell SAC 7 5. Conclusion 8 6. Characteristics of the site 11 7. Assessment of Significance 11 8. Appendix 1 Screening (Heritage) 11 For inspection purposes only. Consent of copyright owner required for any other use. 9. Appendix 2(Archaeological Heritage) 14 10. Screening Conclusion 15 Attachments 16 Archaeological Assessment Drawing No.1 Castletown Geoghegan WWDC 2 Appropriate Assessment Screening EPA Export 26-07-2013:19:22:55 1. Introduction In accordance with the Waste Water Discharge (Authorisation) Regulations 2007 (S.I. No 684 of 2007) Westmeath County Council submitted six Waste Water Discharge Certificate of Authorisation applications to the Environmental Protection Agency (EPA) on and before 22nd December 2009. The Castletown Geoghegan Agglomeration was included within the six submissions. The following report has been produced in accordance with the EPAs correspondence of 7th April 2010 (Notice in accordance with Regulation 25(c) (ii) of the Waste Water Discharge (Authorisation) Regulations 2007) requesting Westmeath County Council to provide further information in accordance with Circular L8/08 ‘Water Services Investment Programmes – Protection of National Heritage and National Monuments’ issued by the Department of Environment, Heritage and Local Government. This report also includes a revised technical summary as stipulated in the original Waste Water Discharge Certificate of Authorisation application submission. 2. Revised Non-Technical Summary Westmeath County Council has previously applied to the Environmental Protection Agency for a Waste Water Discharge Licence for the Waste Water Works at Castletown Geoghegan, Co. Westmeath. The Waste Water Works comprises of a gravity sewer network, a pumping station with storm storage at the Treatment Plant, pumped sewers and the Waste Water Treatment Plant serving the town of Castletown Geoghegan. The Waste Water Treatment Plant was constructed during 2008/2009 and has been recently completed. The Waste Water Works is designed to collect and treat domestic and industrial effluent from a population equivalent of 500. The Waste Water Treatment Plant will treat in the region of 115 cubic metres of effluent at peak design flow every day and For inspection purposes only. ferric dosing provides nutrientConsent removal of copyright owner(phosp requiredhorus for any removal)other use. for the effluent. The works is designed to produce a treated effluent to comply with the following standards: 5 Day BOD 25mg/litre, Suspended Solids 35mg/litre, Total Nitrogen 15mg/l and Total Phosphorus 2mg/l and is discharged to the Monaghanstown Stream at the boundary of the treatment plant site. Currently the works is receiving average flows in the region of 31m³/day and it is estimated that the current population equivalent contributing to the WWTP is 184. The primary discharge from the Waste Water Works is directly to the Monaghanstown Stream (at National Grid Reference 234636E, 243636N) in the townland of Castletown (Moycashel By) Co. Westmeath, which flows into the Monaghanstown River, which in turns flows via the River Brosna. The associated Waste Water Treatment Plant is located at National Grid Reference 234515E, 243679N, also in the townland of Castletown (Moycashel By), Co. Westmeath. There is no storm water overflow associated with the pipe network. However, in the event of flows to the forward flow pumping station at the treatment plant exceed the capacity of the pumps, the excess flows pass to a storm holding tank. If the capacity of the storm holding tank is exceeded, the overflow discharges via the discharge effluent outfall to the Monaghanstown Stream. Castletown Geoghegan WWDC 3 Appropriate Assessment Screening EPA Export 26-07-2013:19:22:55 The Monaghanstown Stream and River are not designated Salmonid water (under the European Communities (Quality of Salmonid Waters) Regulations, 1988) nor is it identified as sensitive water in terms of the Urban Waste Water Treatment Regulations 2001. The stream and river are not designated as an SPA, SAC or NHA. However, as noted above, both the Monaghanstown Stream and River flow into the River Brosna. Two protected sites are located to the east of the Castletown Geoghegan WWTP site, these being Nure Bog NHA and Lough Ennell SAC. The later, Lough Ennell is of significance as a highly productive lake, which supports a rich variety of lower plant and invertebrate species. Its lakeshore habitats, which include alkaline fen, a habitat listed on Annex I of the EU Habitats Directive, support a diverse flora. Lough Ennell is very vulnerable to pollution from agricultural and domestic sources though water quality has been satisfactory in recent years. A deterioration in water quality could affect bird populations (as shown by marked fluctuations in some populations in the past). It is an important amenity area with much of the lake used for fishing, boating and camping. Nure Bog NHA is the closest protected site to the treatment plant site and wastewater discharge location point. The bogland is nationally important as it is raised peatland. Raised bogs are rare within the European Union are under threat nationally from turf cultivation. The Castletown Geoghegan WWTP lies to the east with the receiving water flowing downstream of both Lough Ennell and Nure Bog. The Dry Weather Flow (DWF) in the Monaghanstown Stream (EPA Station 25146 Castletown) is as 0.01m3/sec with a 95%ile flow of 0.03m3/sec. The Dry Weather Flow (DWF) in the Monaghanstown River (EPA Station 25138 Monaghanstown) is as 0.05m3/sec with a 95%ile flow of 0.08m3/sec. The EPA has a river water quality monitoring site at locations on the Monaghanstown River both upstream and downstream For inspection of wher purposese only.the Monaghanstown Stream joins the Consent of copyright owner required for any other use. River. A Q value of 3-4 was recorded both upstream and downstream of this point in 2005. A previous Q value of 4 was recorded upstream in 2002. The River Water Framework Directive status for the Monaghanstown River downstream of Monaghanstown Stream and the River Brosna is 1a; hence it is at risk of failing to meet good status in 2015. The status of the Monaghanstown River upstream of Monaghanstown Stream is 1b, i.e water body thought to be at risk of failing to meet the WFD objective pending further investigations. Based on the effluent design criteria for the site, there are no main potential “threats” to the environment predicted from the operation of the Waste Water Works. Castletown Geoghegan WWDC 4 Appropriate Assessment Screening EPA Export 26-07-2013:19:22:55 3. Management of the Site The Castletown Geoghegan WWTP and its discharge are not directly connected with or necessary to the management of the site. 4. Project Description. The waste water treatment works is designed to cater for a population equivalent (PE) of 500 and is currently accepting effluent flows in the region of 184 PE. A network of gravity sewers collect and transport waste water from the Castletown Geoghegan Agglomeration to the WWTP located south of the village core. Flows from the network drain into an inlet forward feed pumping station. The pumping station is of precast concrete construction and houses duty and standby pumps with the capacity of pumping 8l/s (6DWF) of waste water to the combined screening and grit removal unit. Screening is carried out by two KSK screw clarifiers that separate screenings, sand and grit from the influent and discharge the screenings to bins via ejectors. Post screening the waste water enters the aeration tank. The aeration tank consists of a set of diffusers that defuse air into the liquor for biological treatment. The aerated effluent overflows via a bellmouth from where it gravities to the clarifier tank. Flows enter the clarifier from where the heavier activated sludge settles on the base of the tank. Clarified effluent rises and overflows a V-notch weir from where it gravitates to the outlet flume and is discharged via SW1 to the Monaghanstown stream. The plant is linked to Westmeath County Councils Scada system which records flows and provides an alarm facility in the event of a fault. The system also provides increased monitoring of the treatment plant. The Monaghanstown stream is located For inspection in purposesthe Shannon only. IRBD. The receiving water is Consent of copyright owner required for any other use. not identified as a “sensitive” waterway under the Urban Waste Water Treatment Regulations S.I. 254 of 2001. The receiving water is not classified as a “salmonid river” under S.I. of 1988. Two protected sites are located to the west of the Castletown Geoghegan WWTP site, these being Nure Bog NHA and Lough Ennell SAC. The later, Lough Ennell (Map No.1, page 10) is of significance as a highly productive lake, which supports a rich variety of lower plant and invertebrate species. Its lakeshore habitats, which include alkaline fen, a habitat listed on Annex I of the EU Habitats Directive, support a diverse flora. Lough Ennell is very vulnerable to pollution from agricultural and domestic sources though water quality has been satisfactory in recent years. A deterioration in water quality could affect bird populations (as shown by marked fluctuations in some populations in the past). It is an important amenity area with much of the lake used for fishing, boating and camping.