I/ From: Marian Doyle Environmental Licensing Programme I/ Date: 1 Ot February I

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1 1 To: DIRECTORS I/ From: Marian Doyle Environmental Licensing Programme I/ Date: 1 Ot February I RE: Application for a Waste Water Discharge Licence from Longford County Council, for the agglomeration named Edgeworthstown, Reg. No. D II /I I1 Schedule of discharge licensed: Licence application received: Notices under Regulation 18(3)(b) issued: Information under Regulation 18(3)(b) received: Notices under Regulation 20( 1) issued: Information under Regulation 20( 1) received: Further information received: Site visit & site notice check: Submissions Received: Discharges from agglomerations with a population equivalent of 2,001 to 10, September April June 2009,12 October April July December October 2008 (P. Byrne) None 1. Agglomeration This application relates to the agglomeration of Edgeworthstown, Co. Longford. The town is served by a waste water treatment plant (WWTP) which provides secondary and tertiary treatment. The WWTP, which is in place since 1995 has a design capacity of 2,700 population equivalents (p.e.). In 2007 a new inlet works, picket fence thickener and ferric dosing facility were provided under the Edgeworthstown Sewerage Scheme (Nutrient Reduction). These works were hnded under the Water Services Investment Programme at a cost of 600,000. Longford Co. Co. has no further upgrade works planned at present. The primary discharge is to the River Black, with treated effluent piped lkm downstream of the WWTP. The current agglomeration loading is provided as 1,650p.e., (or 99kgBOD/day) based on a flow and load study in Longford Co. Co. has provided a breakdown into domestic, commerciauinstitutiona1 and industrial loading as shown in Table 1. Longford Co. Co. has assumed a future population growth rate for Edgeworthstown at 2.7% per annum, and estimates an agglomeration loading of approximately 1,885p.e. in five years. Details of planning permissions granted but not commenced were provided accounting for approximately 650p.e. It is considered unlikely that all these developments will proceed. 1

2 Commercial Institutional (schools) I Industrial I 150 I I Total 1,650 There is no tankered waste or landfill leachate discharged to the WWTP. The industrial loading (150p.e.) is said to be from an existing industry C&D Foods Limited, which carries out the manufacture of pet food. Longford Co. Co. noted in their waste water licence application (received 22nd September 2008) that Recent cutbacks at C&D have led to a decrease in the load from the plant. and that they are currently discharging approximately 150 PE. An IPPC licence application from C&D Foods Ltd (assigned Reg. No. PO908-01) was received by the Agency on 04t January The category of the activity is: 6.4(b) of Annex I of the IPPC Directive, treatment and processing intended for the production of food products from: animal raw materials (other than milk) with a Jinished product production capacity greater than 75 tonnes per day. The company has an onsite secondary WWTP, and treated effluent and other wastewaters fi-om the installation are directed to Edgeworthstown WWTP. C&D Foods Ltd submitted monitoring data for their discharge to sewer as part of their IPPC application. In the 12-month period from April 2009 to March 2010 the average discharge was 21 Im3/day and 10.7kgBOD/day (equivalent to 179p.e.). As part of the IPPC licence application process Longford Co. Co. consented to a maximum discharge to sewer of 400m3/day and 80kgBODlday from C&D Foods Ltd (equivalent to 1,333p.e. ). The maximum limits consented to by Longford Co. Co. were included in the Proposed Determination for C&D Foods Ltd issued by the Agency on 30t November As stated the current agglomeration loading is provided as 1,650p.e (from 2007). If C&D Foods Ltd were to expand to their full potential and utilise the maximum allowable loading (1,333p.e.), the combined loading to Edgeworthstown WWTP would be approximately 2,833p.e. This is marginally over the WWTP design capacity of 2,700p.e. Under Condition 1.7 of the RL the licensee shall annually assess the remaining waste water treatment capacity and maintain available capacity to ensure that there is no environmental risk to the receiving waters. Wuste Water Treatment Plant and Collection System Edgeworthstown WWTP is located in Tinnynarr south of the town (See Map 1). Following preliminary treatment (screening and grit removal) flows are split between two aeration tanks. There is ferric sulphate dosing for phosphorus removal at the aeration stage, followed by two clarifier tanks. Tertiary treatment is provided by two trickling filters (stone media) and two tertiary clarifiers, which are fitted with screens to prevent loss of solids. The flows combine at an outlet flume prior to discharge. The plant is manned 5 hourdday, 7 dayslweek. Longford Co. Co. effluent monitoring results fi-om January July 2010 are shown in Table 2. The collection system was constructed in the mid 1990 s and consists of separate foul, storm and combined pipelines. There are no pumping stations and flows are by gravity to the WWTP. Longford Co. Co. states the sewer system is working efficiently. 2. Discharges Primary Discharge The primary discharge is piped lkm to the River Black. The discharge point (SW1) is via a diffuser. The effluent flows are provided as 330m3/day (normal) and 1,529m3/day (maximum). based on GOgBODipersodday 2

3 There is a composite sampler and flow monitor on the WWTP influent and effluent. Monthly monitoring of the final effluent is required in the RL at the WWTP sampling chamber, and samples may be taken on a flow or time based composite sampling basis. The WWTP effluent design standards are 25mg/l BOD, 35mg/l suspended solids and 2mgA total phosphorus. Effluent monitoring results (January July 2010) indicate that the plant is meeting its design standards. Under the Urban Waste Water Treatment (UWWT) Regulations 2001 (S.I. No.254 of 2001 and amendments) the standards required are 25mg/l BOD, 125mg/l COD and 35mg/l suspended solids and in 2009 the agglomeration was compliant with these standards. The River Black is not designated as sensitive under the UWWT Regulations. Also the agglomeration is less than 10,000p.e., therefore the WWTP is not required to comply with the total phosphorus and total nitrogen limits specified under the regulations. Parameter Effluent conc. Mean Note 95%ile Maximum WWTP design standards UWWT Regulations limits BOD COD Suspended Ammonia Total P (mg/l) (mg/l) Solids (mg/l) as N (mg/l) (mg/l) Note 2 (as Total N) Ortho-P (mg ~0~~~ Secondary Discharges No secondary discharges have been identified from the waste water works. Storm Water Ovevflows The WWTP inlet works is designed for 6DWF. Flows up to 3DWF are forwarded for secondary and tertiary treatment, while flows in excess of 3DWF are diverted to a storm tank at the WWTP. The 185m3 tank has the capacity for 3 hours storage at 6DWF. In prolonged storm conditions there is an overflow fi-om the storm tank to the Rwer Black via the primary discharge point (SW1). There is a storm overflow upgradient of the WWTP inlet works (SW2) which outfalls to the River Black. It is said to be activated at flows in excess of 6DWF. Longford Co. Co. estimates the overflow occurrence as 1 hour duration, 3 timedweek for 20 weekdyear, with a discharge of 38m3 per one-hour overflow event. The storm overflow chamber is fitted with a wilks type screen prior to discharge. An additional storm water overflow was identified during the site visit on 15t October 2008, which was not identified in the application. It is located adjacent to Ballymahon Road and also outfalls to the River Black. On the EPA internal GIS there is a storm water overflow at this location with the reference SH-CS00083 (Grid reference: E, N). This SWO has been assigned as SW3 in the RL and is listed in Schedule A.4 Storm Water Overflows. There are no works planned for the wastewater works, however based on the information provided in the application the overflow at SW2 is activated too frequently and needs to be upgraded. Schedule A.4 of the RL requires the SWOs to comply with the DoEHLG design criteria Procedures and Criteria for Storm Water OverJlows, 1995 by 3 ISt December

4 3. Receiving waters and impact assessment Receiving waters The River Black rises in Lisnanagh 2.7km north of Edgeworthstown. It flows southerly and meets the River Inny 12.5km downstream of SW1. The River Black is not designated under the Salmonid Waters Regulations (S.I. 293 of 1988) or the Urban Waste Water Treatment Regulations (S.I. No. 254 of 2001) as amended. There are no public water supply abstractions from the River Black and the nearest abstraction is from the River Inny. Ballymahon public supply abstraction (2000PUB1005 for 1861 persons) is approximately 29km downstream of the primary discharge. Table 3 summarises the main considerations in relation to the River Black downstream of the primary discharge. Table 3. Receiving waters Characteristic Classification Receiving water River Black (26iB05) name and type (WFD code: IE-SH ) Resource use Drinking water abstraction points: Ballymahon (2000PUB1005). Amenity value General amenity. Applicable UWWT Regulations Note Regulations Surface Water Regulations Note Designations None EPA monitoring 26B Ballymahon Rd stations 26B Br nr Ballinlaghta Biological quality 0045 Q3 in 2002, Q2-3 in 2005 rating (Q value) 0100 Q2-3 in 2002 & 2005 WFD Status Note Poor WFD Risk WFD protected areas Any other important issues Note 1: Urban WW la At risk ofnot achieving Good Status Lough Owe1 (Recreational Lake) Comment The River Black rises uis of Edgeworthstown and flows south-easterly to the River Inny. Abstraction fi-om River Inny 29km downstream of primary discharge. Compliant in 2007 & 2008 Non-compliant (see below) 1.5kmupstream of SW1 670m downstream of SW1 There are no more recent Q ratings Objective: Restore to Good status by Risk assigned in km south east of agglomeration, no hydrological connection with River Black discharge. River moderately polluted in Extremely low dilutions for primary upper reaches. Treatment Regulations 2001, S.I. No. 254 of 2001, Urban Waste Water Treatment (Amendment) Regulations Receivina water quality Under the Water Framework Directive the River Black is classed as being of Poor status. In the Inny Water Management Unit Action Plan, part of the Shannon River Basin Management Plan, 2010, there is a proposed exemption for the River Black from achieving Good Status until The River Black has historically had unsatisfactory water quality, in particular in the upper reaches. Ballymahon Rd (EPA station 0045) was seriously polluted from 1987 to 1999, with a marked improvement in In the EPA Interim Report on the Biological Survey of River Quality -Results of the 2005 Investigations, 2006 it states that Some further improvement since 2002 is noted in the lowermost reaches (0400) but for the most of its course from Edgeworthstown the Black River was in a distinctly polluted condition in July Both upstream of the WWTP primary discharge, (0045 Ballymahon Rd) and downstream (0100 Br nr Ballinlaghta) were moderately polluted (Q2-3) in There is no more recent EPA biological data (Q ratings). In monitoring undertaken on behalf of Longford Co. Co. in 2010, both upstream and downstream of SW1 were moderately polluted (43). 4

5 Longford Co. Co. carries out monthly physic-chemical monitoring at Ballymahon Rd (0045) and at Br nr Ballinlaghta (0100). The water quality at both locations is in breach of the water quality standards (mean and 95%ile) for BOD, orthophosphate and ammonia (for Good Status ) stipulated in the European Communities Environmental Objectives (Surface Waters) Regulations, 2009, as shown in Table 4. Longford Co. CO also carries out monitoring 50m upstream and 50m downstream of the primary discharge. See Section 5. Ambient Monitoring. TabIe 4. Summary of ambient monitoring (from August 2009 to May 2010) Orthophosphate Total Ammonia (as N) (2.90) (2.95) mil (95%ile) mg/l (mean) (0.077) (0.16) mg/l(95%ile) mg/l (mean) (0.231) (0.208) mg/l(95%ile) Mass Balance Calculations The assessment of the impact of the WWTP primary discharge is set out below. Table 5 presents results of mass balance calculations using the WWTP design loading of 2,700p.e. (529m3/day) and the emission limit values specified in the RL. The estimated long-term flows for the River Black are 0.052m3/sec (50%ile), 0.01m3/sec (95%ile), and 0.003m3/sec (DWF). These are based on measurements at hydrometric station Lisnagrish, 650m downstream of SWlwhich has a catchment area of 10.8km2. Using the 95%ile river flow and the normal waste water flow associated with 2,700p.e. (529m3/day) there are only 1.6 dilutions available at this location on the River Black. The River Black background concentrations for BOD, ammonia and orthophosphate already exceed the ambient water quality standards upstream of the WWTP at Ballymahon Rd (0045). Therefore or the purposes of this assessment, the wastewater discharge is mass balanced into a notionally clean stretch of river. The approach (formulated by the Office of Environmental Assessment) has been taken, where water quality is already compromised due to other upstream sources (point and diffuse). Ammonia (as N) until 31/12/ from 1/01/

6 i) Biochemical Oxygen Demand Upstream BOD concentrations in the River Black (2.90mgA as a 95%ile) exceeded the EQS of 2.6mg/l, i.e. before consideration of the WWTP discharge. In 2009 the WWTP was achieving effluent BOD concentrations of 3.84mg/l (mean), 10.03mgA (95%ile) and 13.36mgA (maximum) based on applicant data. From the date of grant of licence an ELV of 10mg/l BOD is specified which is considered achievable by the plant. Applying the notionally clean river approach an effluent concentration of 6mgA BOD would be required to meet the ambient water quality standard of 5 2.6mg/l BOD. A limit of 6mg/l is specified in Schedule A.] of the RL to apply from 1 st January to comply with the Surface Waters Regulations. ii) Phosphorus Edgeworthstown WWTP has phosphorus removal (ferric sulphate dosing), provided in late In 2009 the plant was achieving 0.71mgA Total P (95%ile), which is well within its design limit of 2mg/l. The plant was achieving 0.59mg/l orthophosphate for the same period. A limit of 2mgA Total P is specified in the RL. A limit of 0.6mg/l orthophosphate is specified from the date of grant of licence. An effluent concentration of 0.15mg/l orthophosphate would be required to meet the standard of mgll in the River Black and in the RL this shall apply from lst January Condition 5.1 also requires the licensee to reduce phosphorus loading in the discharge to the maximum practicable extent. iii) Ammonia Upstream ammonia levels in the River Black (0.23mgAN) are already exceeding the standard for good status of mg/l as N. There is no WWTP design standard for ammonia but in 2009 the plant was achieving effluent concentrations of 0.46mgAN (mean) and 1.8lmgIlN (95%ile). The ELV specified for ammonia is 2mg/l; however a lower limit of 0.30mg/lN will be required to meet the EQS due to the small number of available dilutions, In the RL this shall apply from 1st January Condition 5.1 also requires the licensee to reduce ammonia loadings in the discharge to the maximum practicable extent. The Shannon River Basin Management Plan ( ) has the objective of restoring the River Black waterbody to Good status by In particular the Inny WMU Action Plan includes the following relevant measures for Edgeworthstown WWTP: - Provide tertiary treatment or relocate outfall - Ensure capacity of treatment plant is not exceeded - Investigation of CSOs. Longford Co. Co. has no plans for the wastewater works. The WWTP primary discharge is piped lkm downstream of the plant to achieve greater dilution however further measures will be required in order to achieving compliance with the Surface Water Regulations. Condition 5.2d) of the RL requires the identification of measures to assist the receiving waters in achieving Good status by This may involve relocating the outfall for the primary discharge. The emission limit values required to be achieved in the RL by 3 lst December 2014 would not be relevant if the licensee proposed to relocate the primary discharge, and a licence review would be required. The Rwer Black is classified as being of Poor status under the WFD and is moderately polluted upstream of the agglomeration. Pollution from sources in the upstream catchment must be dealt with under the programme of measures identified in the Shannon River Basin Management Plan. 4.Site Visit A site visit of the agglomeration was carried out on 15t October The visit focused on the waste water treatment plant and storm water overflows. The WWTP appeared to be operating satisfactorily at the time of the visit. 6

7 5. Ambient Monitoring Schedule B.4 of the RL sets out the requirements for monitoring of the River Black with ten samples per year. The upstream monitoring location is EPA Station 0045 Ballymahon Rd. The downstream location provided by Longford Co. Co. (MP3) is 50m d/s of the primary discharge (SWI) and may be within the mixing zone of SW1. The RL requires monitoring at EPA station 0100 Br nr Ballinlaghta (670m downstream of SWl), which is considered to be a more appropriate location. Under Condition 4.16 where results are available from any other statutory body (including the Agency), these can be in part fulfilment of Schedule B.4. An annual Small Stream Risk Score assessment or Q rating are required to determine the effects on the biological quality of the river. 6. Combined Approach The Waste Water Discharge Authorisation Regulations, 2007 (S.I. No. 684 of 2007) as amended specify that a combined approach in relation to licensing of waste water works must be 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.I. No. 254 of 2001) as amended and the limits determined under statute or Directive for the purpose of achieving the environmental objectives established for surface waters, groundwater or protected areas for the water body into which the discharge is made. The RL as drafted gives effect to the principle of the Combined Approach as defined in S.I. No. 684 of Programme of Improvements Longford Co. Co. has no planned improvement works for Edgeworthstown WWTP or for the waste water works. Condition 5.2d) of the RL requires the licensee to identify the most appropriate measures (including measures specified in the Shannon River Basin Management Plan) to assist in achieving Good status by The RL in Schedule A. 1 also specifies limits for the primary discharge with more stringent limits, which shall apply from lst January Schedule C. I also specifies improvement works for the WWTP to be completed by 31 st December The above requirements have been discussed with the DoEHLG Inspector, who considers this approach is appropriate. 8. Compliance with EU Directives In considering the application, regard was had to the requirements of Regulation 6(2) of the Waste Water (Discharge) Authorisation, Regulations, 2007 (S.I. No. 684 of 2007) notably: Drinking Water Abstraction Regulations There are no drinking water abstraction points downstream on the River Black. There is an abstraction fkom the River Inny 29km downstream of primary discharge for Ballymahon (2000PUB1005). Sensitive Waters The River Black is not designated as sensitive under the Urban Wastewater Treatment Regulations. Water Framework Directive [2000/60/EC] The RL, as drafted, transposes the requirements of the Water Framework Directive. In 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. However these will not be sufficient to comply with the standards required for Good status. The Shannon River Basin Plan requires restoration of the River Black waterbody to Good status by In the Inny WMU Action Plan Edgeworthstown WWTP is listed under Capital Works with the measure to Provide tertiary treatment or relocate outfall and the measure to Ensure capacity of treatment plant is not exceeded. It also listed under the measure Investigation of cso s. 7

8 As stated Longford Co. Co. are required (in Condition 5.2d)) to identify the most appropriate measures necessary to assist receiving waters in achieving Good Status by The requirements for storm water overflows are addressed in Schedule C.2. European Communities Environmental Objectives (Surface Water) Regulations 2009, S.I. No. 272 of 2009 The River Black does not comply with the water quality standards (for Good Status ) stipulated in S.I. No. 272 of 2009 either upstream or downstream of the WWTP primary discharge. The RL, as drafted, has regard to the requirements of S.I. No. 272 of 2009, with emission limit values set from the date of grant of licence and tighter limits shall apply from 1 St January20 15 to enable compliance with the regulations. The conditions and emission limit values specified in the RL should contribute towards no further deterioration in the receiving waters as a result of the discharges from the agglomeration. Urban Waste Water Treatment Directive [91/271/EECI Edgeworthstown WWTP currently provides an adequate level of treatment for compliance with the UWWT Regulations, i.e., secondary treatment for discharges >2,000p.e. by 3 lst December The RL has regard to the requirements of the UWWT Directive, specifically with regard to emission limits and monitoring requirements. In particular, Condition 3 Discharges provides conditions regulating discharges to waters and Schedule A: Discharges specifies limit values for substances contained within the discharges. Bathing Water Directive [2006/7/EC1 There are no bathing waters in the vicinity of discharges from the agglomeration. EC Freshwater Fish Directive r2006/44/eci There are no designated salmonid waters in the vicinity of discharges from the agglomeration. Shellfish Waters Directive r2006/113/eci There are no designated shellfish waters in the vicinity of the agglomeration. Dangerous Substances Directive [2006/11/ECI The applicant has provided sampling results for dangerous substances in the primary discharge (SWl), ASW-lu (upstream of SWl) and ASW-1dMP3 (50m downstream of SWl). The results have been compared to the Environmental Objectives (Surface Waters) Regulations For tributyltin the laboratory limits of quantification were not sufficient to determine compliance with the standard of O.OOlpg/l. Upstream of SW1 had a dichloromethane level of 22pg/l compared to the EQS of 20pg/l (as an annual average). Dichloromethane is a volatile organic compound and can originate from petrol vehicles and processes using solvents. Condition 4.10 of the RL specifies hrther screening of the primary discharge as required by the Agency. Birds Directive [79/409/EEC1 & Habitats Directive [92/43/EEC1 There are no discharges from the agglomeration directly into any site designated under the E.U. Habitats Directive or the Birds Directive. The applicant conducted a Stage 1 Screening of the impact of the discharge from the agglomeration on key species and habitats. The flow chart and methodology in the DoEHLG Circular L8/08 was used. It was concluded that there would be one Natura 2000 site potentially affected by effluent and water quality in the river Black, Glen Lough Special Protection Area (004045). Glen Lough is designated under the Birds Directive. It is also a proposed Natural Heritage Area (pnha); site code The River Black meets Glen Lough approximately 5.6km downstream of the WWTP primary discharge. From the SPA site synopsis extensive drainage in the 1960s has resulted in a dramatic drop in the water table here, with the result that there is now little open water, except dziringflooding in the winter months. The SPA site attracts a range of wintering waterfowl but the principal interest is the internationally important Whooper Swan population based in the area. The Whooper Swan is listed on Annex I of the Birds Directive. Greenland White-fronted Goose, also listed on Annex I is said to be an occasional visitor. 8

9 Encironmental Liabilities Directice The RL. as drafted. Condition 7.2, satisfies all the requirements of the Environmental Liabilities Directike in particular those requirements outlined in Article 3(1> and Annex 111 of 2 004!?~~ 9. Cross Office Liaison Ahice and guidance issued bj the Technical Working Group (1WG) was followed in my assessment of this application. Advice and guidance issued by the TWG is prepared through a detailed cross-office co-operative process, with the concerns of all sides taken into account. The Board of' the Agency has endorsed the advice and guidance issued by the I'CVG for use by licensing Inspectors in the assessment of wastewater discharge licence applications. The EPA Hydrometric Section was consulted to confirm the flow data for the River Black. 10. Submissions No submissions were received in relation to this application. 11. Charges The RL sets an annual charge for the agglomeration at 3, and is retlective of the monitoring and enforcement regime being proposed for the agglomeration. 12. Recommendation 1 recommend that a Final Licence be issued subject to the conditions and for the reasons as set out in the attached Recommended Licence. Signed

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11 Map 1: Edgeworthstown Agglomeration 10

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