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2 Finnea Agglomeration Wastewater Treatment Plant Waste Water Certificate of Authorisation Application (Register Number A ) Regulation 24 Compliance Requirements County Buildings Mullingar Co. Westmeath Phone: Fax:

3 1. Clarify the name of the agglomeration. Two possible names were given in the Certificate of Authorisation application form; Finnea or Hillside. The agglomeration to which the waste water discharge certificate of authorisation relates to is called Hillside-Finnea Agglomeration. 2. Confirm the design capacity of the waste water treatment plant and the current population equivalent (P.E.) being treated at the plant. Please confirm that the current pe includes the maximum average weekly loading for the agglomeration having taken account of local festivals, peak holiday seasons, etc. The existing waste water treatment plant is designed to cater for a population equivalent of 80PE. The maximum average weekly loading contributing to the plant is 36 PE for the Finnea agglomeration. 3. Please submit all relevant details requested under Section C: Infrastructure & Operation, of the application form. Include information on the operation of the Waste Water Treatment Works for the above named agglomeration. A response to this requirement is attached on page 4 of this document. 4. Provide an appropriately scaled drawing indicating the location of the primary discharge point. The primary discharge point is shown in the attached Drawing No.3 5. Provide a non technical summary of the application A response to this requirement is attached on page 2 of this document. 1

4 Section A: Non Technical Summary Westmeath County Council is applying to the Environmental Protection Agency for a Waste Water Discharge Certificate of Authorisation for the Waste Water Works at Finnea, Co. Westmeath serving the Hillside local authority housing scheme. The Finnea waste water network comprises of a small combined gravity sewer and the associated package waste water treatment works. The waste water treatment plant (WWTP) consists of one concrete treatment unit. The unit incorporates a primary settling chamber, aeration chamber, final settlement area and subsequent percolation area. The Finnea Waste Water Treatment Plant (WWTP) was constructed to serve a small local authority housing scheme. The plant serves 12 domestic dwellings sited within close proximity of the plant site. The WWTP is designed to accept and treat effluent from a population equivalent of 80PE. The plant currently accepts waste from a population equivalent of 36PE. Currently the treated effluent concentrations are as follows, average BOD concentrations of 32.5mg/l, COD concentration of 114mg/l and an average suspended solids concentration of 17 mg/l. The Primary discharge for the plant flows directly to an adjacent percolation area at National Grid Reference (NGR) E, N in the townland of Finnea, Co. Westmeath. There is no emergency overflow or storm water overflow facility located within the treatment plant site boundary. All discharges form the plants are directed through the primary discharge point to the percolation area. Ground water quality in the townland of Finnea is recorded as having a Good status however there are no groundwater monitoring locations sited within close proximity or upstream and downstream of the treatment site. There are three designated sites located within five kilometres of the waste water treatment site. These are Lough Sheelin (Special Protection Area), Moneybeg and Clareisland Bogs (Special Area of Conservation) and Lough Kinale & Derragh Lough (National Heritage Area and Special Protection Area). This designated sites are important in terms of supporting a variety of wildlife and in the conservation of wild birds notably Loughs Sheelin, Kinale and Derragh Following appropriate assessment screening in accordance with Waste Water Discharge Licensing Appropriate Assessment and The DoEHLG Circular L8/08 Protection of Natural Heritage and National Monuments it was deemed that there is no negative impact upon the designated sites. 2

5 Section B8 (i): Population Equivalent of Agglomeration The agglomeration of Hillside-Finnea covers only Hillside local authority housing scheme which comprise of 12 domestic dwelling. The agglomeration is shown is drawing 1. The existing population equivalent of the agglomeration is 36 PE. The existing population equivalent has been calculated based upon an average occupancy rate of 3 persons per dwelling Name BOD Loading kg/day Hydraulic Loading m³/day Population Equivalent (P.E.) Domestic Houses Total The above results for the BOD and Hydraulic loadings were derived from the EPA s Wastewater Treatment Manual for Small Communities, Business, Leisure Centres and Hotel. Section 2.4: Substrate loading from domestic premises was used to estimate the expected hydraulic loading and BOD loading during the summer month. A hydraulic loading of 225 litres per day per person and a BOD loading of 60g per day per person were used in the estimation. The two figures are recommended for combined sewer. 3

6 Section C: Infrastructure & Operation C.1 Operational Information Requirements. C.1.1 Waste Water Treatment Plant The Finnea Waste Water Works is sited in the village of Finnea, Co. Westmeath. The treatment facility serves a local authority housing development located in Finea Village and has a wastewater treatment design capacity of 80p.e. Currently the plant accepts and treats wastewater form a population equivalent (P.E.) of 36. The treatment facilities comprise of the following elements. A network of 150mm diameter gravity sewers within the Hillside Local Authority housing development. A 3kw.Packaged Blower to provide aeration to the aeration chamber. A packaged treatment system consisting of 4 treatment chambers, settling chamber, aeration chamber, anoxic camber and clarifying chamber Sludge return pumps in the clarifying chamber Percolation area The Waste Water Works discharges directly into ground water through the percolation area in the townland of Finnea, Co. Westmeath. The associated Waste Water Treatment Plant is located in the townland of Finnea, Co. Westmeath. The agglomeration incorporates 12 residential houses that are served by the WWTP. A 150mm diameter upvc sewer network directs foul flows within the agglomeration to the treatment plant. The Finnea Packaged Wastewater Treatment Plant (WWTP) is capable of providing treatment for a design load of 80 population equivalent. The packed WWTP comprises of four treatment chambers. The first chamber is designed to act as a primary settlement tank removing most of the solids and allowing a limited amount of anaerobic digestion to occur. The waster water then flows over the weir into the second chamber. The second chamber houses the aeration system. The air is introduced by packaged blower through pipe diffusers. After aeration the wastewater flows over the weir into the third chamber where denitrification occurs under anoxic conditions The wastewater then flows over the weir to clarifying chamber which serves as a secondary clarifier. Conditions in the clarifying chamber are quiescent and allow sedimentation of suspended solids to take place. A sludge pump returns activated sludge from the clarifying chamber to the settling chamber. Treated effluent from the clarifying chamber flows over a weir to the percolation area. The schematic arrangement of the Wastewater Treatment Plant is shown in Drawing No.3. The design criteria for the plant are shown below in table

7 PLANT DESIGN CRITERIA Design Population Equivalent 80 PE Design Daily flow rate 18 m 3 /day Design Daily maximum flow rate 4.6 m 3 /hour Maximum BOD 5 loading 4.8 kg Treated effluent Standards BOD 5 20mg/litre Suspended solids 30mg/litre Table 1.0 Monitoring of the treated effluent occurs at a sample tap located on the aeration tank. Currently this is the only sampling location within the plant site. There are no monitoring points at the percolation area which is situated within a green area in the housing development. C.1.2 Storm Water Overflows There are no storm overflow structures associated with the existing wastewater treatment plant or attached collection network. The collection network is limited to the Hillside Local Authority housing scheme. C.1.3 Pumping Stations There are no independent pump stations operating within the agglomeration. 5

8 Appendix A: Drawing Attachment Drawing No Title Revision Date Drawing No. 1 Hillside-Finnea Agglomeration Map - 25/01/2011 Drawing No. 2 WWTP Location Map - 25/01/2011 Drawing No. 3 Primary Discharge Point GW1-25/01/2011 Drawing No. 4 WWTP Schematic Layout - 25/01/2011 6

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