PLANNING REPORT. For inspection purposes only. MOUNTMELLICK WASTEWATER TREATMENT PLANT PART 8 PROCEDURE

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1 PLANNING REPORT MOUNTMELLICK WASTEWATER TREATMENT PLANT PART 8 PROCEDURE Donal Kiely Senior Executive Planner John Daly Director of Services Pursuant to Part VIII of the Planning & Development Regulations 2001 this report is submitted to the members of Laois County Council. In accordance with Section 179 (3)(a) of the Planning & Development Act, 2000 it is proposed to proceed as indicated in Section 6 of this report. Gerry Gibson Deputy County Manager

2 TABLE OF CONTENTS 1.0 Foreword. 2.0 Description of the Nature and Extent of the Proposed Development. 3.0 Likely Implications, if any, with respect to the Proper Planning and Development of the area. 4.0 Persons or Bodies who made Submissions or Observations with respect to the Proposed Development. 5.0 Summary of Issues Raised by Persons or Bodies who made Submissions or Observations with respect to the Proper Planning and Development of the Area. Local Authority Response to the Issues Raised. 6.0 Action Proposed.

3 1.0 Foreword. This Planning Report has been prepared pursuant to Section 179 of Part XI, of the Planning and Development Act, 2000, and Sections 81, 82, 83 and 84 of Part VIII S.I No. 600 of 2001 Planning and Development Regulations. 2.0 Description of the Nature and Extent of the Proposed Development. 2.1 Upgrading works are proposed at the existing wastewater treatment plant (WWTP) in Mountmellick. This work is being carried out as part of the Mountmellick Sewer Extensions Scheme which also involves the upgrading of existing pump stations located in Mountmellick town [at Irishtown, Connolly Street and Emmett Terrace]. At present the WWTP serving Mountmellick has a design population equivalent (p.e.) of 7,000. Due to the significant overloading of the plant Laois County Council wish to undertake works to provide storm storage at the plant and to increase the biological treatment capacity in the oxidation ditch. Additionally the works include for the construction of a control/administration building. The proposed upgrading works at the WWTP in Mountmellick will improve the treatment of the town s wastewater by: Facilitating the diversion of inlet flows from the existing inlet works to a proposed storm inlet overflow chamber. Inlet flows greater than 60l/s will be stored at a proposed storm attenuation tank and returned for full treatment as soon as the flow has returned to normal. 2.2 EXISTING SYSTEM. The existing WWTP consists of an inlet screen, grit channels, an aeration tank, 2 No. clarifiers, a sludge treatment facility and a control building. The existing plant is overloaded and upgrades at the treatment plant are required. 2.3 OUTLINE DESCRIPTION OF THE WORKS The Mountmellick Wastewater Treatment Works contract will be procured under the Minor Works Contract for the provision of Building and Civil Engineering works designed by the Employer published by the Department of Finance. The proposed wastewater treatment works will be constructed within the boundary site of the existing WWTP Flows greater than 60 l/sec arriving at the WWTP will overflow to the proposed stormwater attenuation tank. The tank contains two chambers, which fill in series and empty in parallel. Effluent from the tank shall discharge over a weir into the

4 outlet channel. When a storm abates, stormwater retained in the tank shall be returned to the storm inlet overflow chamber, by pumping, to receive full treatment. The proposed administration/control building includes welfare facilities, storage and a control room to accommodate a SCADA system for the treatment works and outlying pump stations located within Mountmellick town. Additionally it is proposed to construct an emergency overflow, 44 metres in length from the proposed storm attenuation tank to the Owenass River adjacent to the wastewater treatment plant. 3.0 Likely Implications, if any, with respect to the Proper Planning and Development of the area. The proposed upgrades to the WWTP are confined to within the site curtilage of the WWTP. The overall visual impact of the proposed scheme is considered to be minimal and consistent with the existing plant and infrastructure. The proposed administration\control building is restricted to a maximum height of 4.3 metres above the existing ground level as shown on Drawing No A-PP-05. All tanks and other process structures shall be buried or partially buried so that no more than 2.3 metres projects above the finished ground level. Passive carbon odour control units will be installed within each chamber of the stormwater attenuation tank to mitigate against odour. Additional hardstanding on the site will have a bitumen macadam surface and be kerbed to form roadways and turning areas. 4.0 Persons or Bodies who made Submissions or Observations with respect to the Proposed Development. No third party / public submissions have been received in response to this Part VIII. 5.0 Summary of Issues Raised by Persons or Bodies who made Submissions or Observations with respect to the Proper Planning and Development of the Area. Local Authority Response to the Issues Raised. None received. 6.0 Action Proposed. The proposed development will ensure a more robust foul drainage infrastructure for Mountmellick to meet the current and future demands of

5 the town It will accord with the proper planning and sustainable development of the area. It is proposed to proceed with the proposed development subject to proper planning and sustainable development practices.

6 COMHAIRLE CHONTAE LAOISE LAOIS COUNTY COUNCIL Application to the Environmental Protection Agency for a Waste Water Discharge Licence In accordance with Part 111 of the Waste Water Discharge (Authorisation) Regulations 2007 (S.I. No. 684 of 2007) Laois County Council, Aras an Chontae, JFL Avenue, Portlaoise, County Laois, hereby gives notice of its intention to apply for a Waste Water Discharge Licence for the Mountmellick Waste Water Treatment Plant. The Waste Water Works includes the collection and conveying systems, preliminary and secondary treatment. Location: Mountmellick Waste Water Treatment Plant, Bay Road, Mountmellick, Co. Laois. National Grid Reference for Mountmellick Waste Water Treatment Plant: E N National Grid Reference for plant primary discharge: E N As soon as is practicable after the submission of the application to the Environmental Protection Agency on the 22 nd September, 2008 a copy of the application (in the format determined by the Environmental Protection Agency) along with such further information relating to the application as may be furnished to the Agency in the course of the Agency s consideration of the application will be available for inspection or purchase during normal office hours at the following locations: The Environmental Protection Agency, Headquarters, PO Box 3000, Johnstown Castle Estate, County Wexford (053) Laois County Council, Aras an Chontae, JFL Avenue, Portlaoise, Co. Laois (057) A submission in relation to the waste water discharge licence application maybe made in writing or via to the Environmental Protection Agency, P.O. Box 3000, Johnstown Castle Estate, County Wexford info@epa.ie. Signed: E. Kenny Date: 05 th September, 2008 Assistant Engineer Water Services

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22 C1 - Flow Diagram Existing Plant Mountmellick WWTP Existing Plant INLET PRELIMINARY TREATMENT OXIDATION DITCH RAS SETTLING TANKS (CLARIFIERS) Effluent WAS SW 1 SLUDGE DEWATERING RIVER OWENASS SLUDGE REMOVAL EPA Export :02:12:58

23 C2 - Mountmellick Flow Diagram Upgraded Plant Mountmellick WWTP Upgraded Plant INLET INLET STORM WATER ATTENUATION TANK PRELIMINARY TREATMENT OXIDATION DITCH RAS SETTLING TANKS (CLARIFIERS) Effluent WAS SW 1 SW 2 SLUDGE DEWATERING RIVER OWENASS SLUDGE REMOVAL EPA Export :02:12:58

24 DISCHARGE POINTS PT_CODE PT_TYPE LA NAME RWB_TYPE RWB_NAME DESIGNATION EASTING NORTHING SW 1 Primary Discharge Laois River Owenass Special Area of Conservation (SAC ) SW 2 Storm Water Overflow (Upgraded plant) Laois River Owenass Special Area of Conservation (SAC ) SW 3 Storm Water Overflow (network) Laois River Owenass Special Area of Conservation (SAC ) SW 4 Storm Water Overflow (network) Laois River Owenass Special Area of Conservation (SAC ) SW 5 Storm Water Overflow (network) Laois River Owenass Special Area of Conservation (SAC ) SW 6 Storm Water Overflow (network) Laois River Owenass Special Area of Conservation (SAC ) WWDL D2 - MOUNTMELLICK DISCHARGE POINTS EPA Export :02:12:58

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26 WWDL E2b Mountmellick Monitoring Programme Laois County Council Monitoring Programme On a monthly basis Inlet and outlet -24hr composite samples or grab samples Upstream and Downstream Grab Samples Analysis methods All are documented in house methods based on Standard methods for the examination of water and wastewater 20 th Edition Parameter Method Basis of method ph Electrometric measurement Based on APHA H + B (1998) Conductivity Conductivity measurement Based on APHA 2510 B (1998) Suspended Solids Gravimetric Based on APHA 2540 D (1998) Biochemical Oxygen 5 Day test Based on APHA 5210 B Demand Chemical Oxygen Demand Dissolved Oxygen Hardness (as CaCo 3 ) Nitrite (as N) Nitrate (as N) Total Oxidazible Nitrogen (TON) Reactor Digestion method Dissolved Oxygen measurement Aquachem 250 autoanalyser Spectrophotometry Aquachem 250 autoanalyser Spectrophotometry Aquachem 250 autoanalyser Spectrophotometry Aquachem 250 autoanalyser Spectrophotometry (1998) Based on APHA 5220 D (1998) Closed Reflux Colourmetric method Based on APHA 4500-O (1998) Based on APHA 2340 C (1998) Based on APHA NO2 B (1998) Based on APHA NO2 B (1998) Based on APHA NO2 B (1998) Orthophosphate Total Phosphorus Chloride Aquachem 250 autoanalyser Spectrophotometry Acid Persulphate Digestion./Phos Ver 3 Aquachem 250 autoanalyser Spectrophotometry Based on APHA 4500-P E (1998) Based on APHA 4500-P E (1998) Based on APHA Cl- E (1998) EPA Export :02:12:58

27 Quality control When samples arrive at the lab they are logged and given unique reference numbers. Quality control standards are run with every batch of analysis that is required. The Auto analyser spectrophotometer is calibrated everyday before use and Quality control samples are pre-programmed to run at selected intervals. Results are recorded into laboratory log books Results are transcribed to the results database, which are then checked/certified before being published to the live database. Laois County Council participates in the EPA Intercal scheme. Calibration and Maintenance A calibration schedule is maintained and each price of equipment is externally calibrated on an annual basis. The Aquachem 250 auto-analyser has a maintenance contract in place and is serviced on an annual basis. Capital Expenditure budgets are reviewed annually for replacement equipment. EPA Export :02:12:58