Whitegate PWS (Dower Spring)

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1 Water Framework Directive Groundwater Monitoring Programme Site Information Whitegate PWS (Dower ) ImagePath1: Whitegate PWS (Dower )\ (b)_(800_x_600).jpg Whitegate PWS (Dower ) is a spring used as a public water supply. The abstraction rate is 4500 m³/day. The GSI has completed a source report for the site. August 2011

2 Site Name: RBD: Site Use: Whitegate PWS (Dower ) SWRBD Easting: Northing: Drinking Water (PWS) Hydrometric Area: 19 Townland: Ownership: Water Quality Monitoring Network: DOWER County Council SITE INFORMATION County: EU Reporting Code: IE_SW_G_058_04_026 GWB Name: Midleton 1 GWB Code: Drinking Water Code: Water Level Monitoring Network: The Dower is located about one mile east-southeast of Castlemartyr. Level IE_SW_G_ PUB2407 Surveillance Operational (Point) Operational (Diffuse) N N Y N Flow Y Site Comments: Location and Access Information: SITE DIRECTIONS The Dower is located about one mile east-southeast of Castlemartyr. The spring emerges from a cave in a low limestone cliff on the south side of a minor road. Additional Comments: Monitoring Point Type: Borehole Log Available: Top of Casing (m agl): WELL INFORMATION Abstraction Rate (m³/d): 4500 Ground Elevation (m OD): 9 Total Drilled Depth (m bgl): n/a Depth to Bedrock (m bgl): Upper Casing Diameter (mm): Lower Casing Diameter (mm): Final Borehole Depth (m): Upper Casing Bottom Depth (m bgl) : Lower Casing Bottom Depth (m bgl): Screen Interval (m bgl): Grout Type (cement,bentonite): Screen Type (PVC,Steel,other): Screen Slot Size (mm): Grouted above (m bgl): Grout Volume Injected (m³): Gravel Pack Interval (m bgl): Potential Yield (m³/day): Gravel Pack Volume (m³): Open Hole Interval (m bgl): Specific Capacity (m³/d/m): Comments on Monitoring Site: Static Water Level (m bgl): 7 Scheme Name: Source Report Info: Whitegate Regional Number of Abstraction Points in the Scheme: Source report prepared by GSI and revised in Source Report Available Y Scheme Summary: The scheme consists of one spring. The Dower is located about one mile east-southeast of Castlemartyr. The spring emerges from a cave in a low limestone cliff on the south side of a minor road. Static water level in the spring is approximately 7 m. Page 2 of 5

3 HYDROGEOLOGY GEOLOGY Soil: Subsoil: Bedrock: Deep well drained mineral (AminDW) Tills (diamictons) (TDSs) Dinantian Pure Unbedded Limestones Subsoil Permeability: n/a HYDROGEOLOGY ZONE OF CONTRIBUTION Aquifer Category: Estimated ZOC Size (): ZOC Delineation Comments: Vulnerability at Monitoring Extreme Flow Regime: Karstified site: 20.1 ZOC Delineated By: Recharge Est Recharge (mm/yr): Estimate (mm/yr): The GSI delineated a ZOC based on discharge rate, recharge and topography. See the source report for details. GSI 236 Groundwater Vulnerability within ZOC (% area): Extreme (X) 8.81 Extreme (E) High Moderate Low 0 High to Low 0 Unclassified 0 Hydrochemical Signature: Alkalinity (mg/l HCO3): Hardness (mg/l CaCO3): Conductivity (us/cm): Monitoring Record Period: Pressure (e.g., Nitrates, Phosphates, Abstractions): Average: 214 Average: 247 Average: 519 From: 2007 Ca-HCO3 Diffuse Range: Range: Range: To: 2010 HYDROCHEMISTRY Additional Water Chemistry Information: RISK ASSESSMENT Typical Contaminants: During the monitoring period: The average nitrate concentration was 31 mg/l NO3 and the maximum nitrate concentration was 39 mg/l NO3. The average ammonium concentration was mg/l N and the maximum ammonium concentration was 1.77 mg/l N. The average molybdate reductive phosphorus (MRP) concentration was mg/l P and the maximum MRP concentration was mg/l P. The average chloride concentration was 30.6 mg/l Cl and the maximum chloride concentration was 42.1 mg/l Cl. Phosphate Risk Category: At risk, high confidence GWB Status: Good Impact Potential within ZOC (% area): Extreme: 5.35 High: Moderate: Low: 0.00 Negligible: 2.26 OTHER INFORMATION Page 3 of 5

4 Pump House Sampling Point Page 4 of 5

5 Data Summary Sheet - July 2011 Disclaimer: The data in this document are based on the best available information and understanding at time of writing. Neither the Environmental Protection Agency, nor the individual bodies supplying data for this document and accompanying maps will be responsible for any loss or damage from the use or interpretation of these data. Rock Unit Geology Map: GSI, 2009 Aquifer Type Map: GSI, 2009 Groundwater Vulnerability Map: GSI, 2009 Soils & Subsoils Type: Teagasc, 2007 Recharge Map: GSI, 2009 Impact Potential Map: EPA, 2009 Risk Assessment Map: EPA WFD Risk Assessment, 2006 Groundwater Body Status: EPA WFD Status Assessment, 2008 Water Quality Data: EPA WFD Monitoring, 2008 Groundwater Threshold Values Groundwater threshold values for selected parameters: Nitrate - General Chemical Test/ Drinking Water Test (37.5 mg/i N03) Ammonium - Drinking Water Test (0.175 mg/i N) / Surface Water Test (0.065 mg/l N) Molybdate Reactive Phosphorus (MRP) - Surface Water Test (0.035 mg/i P) Chloride -Saline/Intrusive Test (24 mg/i) / Drinking Water Test (175 mg/i Cl) Electrical Conductivity -Saline/Intrusive Test (800 µs/cm) / Drinking Water Test (1,875 µs/cm) Further information on groundwater threshold values is contained in the Groundwater Regulations (S.I. No.9 of 2010). General Downgradient Distances General Downgradient Distances (XL) applied to boreholes sourced in bedrock aquifers are constrained to estimate approximate limits based on data at the GSl. ln some cases they may be higher or lower depending on local conditions. Rk,, Lk Lm, PI 225 m 150 m 60 m It is assumed that groundwater downgradient of a spring cannot flow back up to the spring, however a precautionary 30m buffer is generally applied which allows for instances where pumping under dry weather periods may induce a drawdown or where the ground may be sloping toward the spring from the downgradient side. Version 0: Version 1: Version 2: Version 3: Version 4: Prepared by GSI Date: Prepared by OCM (DC) Date: Feb 2011 Prepared by Date: Prepared by Date: Prepared by Date: Page 5 of 5

6 Enclosed Depression &. 0500PUB2407 / IE_SW_G_058_04_026 Location Map for Whitegate PWS Abstractions

7 0500PUB2407 / IE_SW_G_058_04_ Aquifer Category Map for Whitegate PWS Abstractions Fault Enclosed Depression

8 Bedrock Map for Whitegate PWS 0500PUB2407 / IE_SW_G_058_04_026 Abstractions Dinantian Mudstones and Sandstones ( Group) Devonian Old Red Sandstones Dinantian Pure Bedded Limestones Enclosed Depression Dinantian Lower Impure Limestones Dinantian Pure Unbedded Limestones Fault

9 Enclosed Depression &. 0500PUB2407 / IE_SW_G_058_04_026 Groundwater Vulnerability Map for Whitegate PWS Abstractions E (Rock near surface or Karst) M (Moderate) Water E (Extreme) L (Low) No Data H (High) HL (unmapped - High to Low)

10 Enclosed Depression &. 0500PUB2407 / IE_SW_G_058_04_026 Subsoils Map for Whitegate PWS Abstractions Bedrock outcrop or subcrop Till derived from limestones Alluvium Made ground Water Gravels derived from Devonian sandstones Till derived from Devonian sandstones

11 Enclosed Depression &. 0500PUB2407 / IE_SW_G_058_04_026 Soils Map for Whitegate PWS Abstractions Acid Deep Well Drained Mineral Acid Shallow Poorly Drained Mineral Basic Shallow/Rocky/Peaty Mineral Acid Deep Poorly Drained Mineral Acid Shallow/Rocky/Peaty Mineral Mineral Alluvium Acid Poorly Drained Peaty Mineral Basic Deep Well Drained Mineral Made Acid Shallow Well Drained Mineral Basic Shallow Well Drained Mineral Water