Silliot Hill Integrated Waste Management Facility Kilcullen, Co. Kildare. Quarterly Report: Groundwater. Report Period Q1: January 2017 March 2017

Transcription

1 Silliot Hill Integrated Waste Management Facility Kilcullen, Co. Kildare. Quarterly Report: Groundwater Report Period Q1: January 2017 March 2017 Waste Licence Reg: W Original Prepared by: Kildare County Council, Aras Chill Dara, Devoy Park, Naas, Co. Kildare. July 2017

2 1. GROUNDWATER QUALITY 1.1 Monitoring Locations The quarterly groundwater monitoring is carried out in accordance with Waste Licence Ref: W , at the locations outlined in the Drawing of Monitoring Locations (Appendix I). 1.2 Monitoring Parameters Groundwater samples were analysed for quarterly parameters as outlined in Table D.5 of Schedule D of the Waste Licence Ref: W Monthly measurements of groundwater elevation were also taken, as per the licence. Sampling was conducted on 9 th May 2017 and 11 th May Monitoring Results Quarterly Chemical Analysis Groundwater Well laboratory analytical results were compared where applicable, to the relevant standards in the Statutory Instrument S.I. No. 9 of 2010: European Communities Environmental Objectives (Groundwater) Regulations 2010, as amended 2012 (S.I. No. 149 of 2012). The Interim Guideline Values (IGVs) for Groundwater from the Environmental Protection Agency (EPA) report Towards Setting Guideline Values for the Protection of Groundwater; Interim Report (2003) were used in the absence of groundwater standards for specific parameters. Private well laboratory analytical results were compared to Water Quality Standards set in S.I No. 278 of 2007 European Communities (Drinking Water) (No.2) Regulations, It should be noted that these standards are presented for guideline purposes only and do not relate specifically to groundwater quality standards. A sample could not be obtained from BH15-07, BH16-07 and BH16R as they had insufficient volumes of water to sample. Results of quarterly chemical monitoring of groundwater and private wells are shown in Table 1.1 and Table 1.2 respectively.

3 BH1 BH2 BH3 BH4-07 BH9D BH10D BH11D KTK20 BH13-07 GWR1 GWR2 GWR3 Table 1.1: Quarterly Parameters for Groundwater Wells, Q Parameter GTV Note 1 IGV Note 2 ph (ph units) Conductivity 20 o C) Ammoniacal Nitrogen (as N) (mg/l) < < < Iron (µg/l) Potassium (mg/l) Sodium (mg/l) Chloride (mg/l) TON (as N) (mg/l) 1.61 < < < ~ Total Phenols (µg/l) <0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5 < TOC (mg/l) < < <1 <1 <1 < <1 <1 ~ Total Coliforms (cfu/100ml) <1 Faecal Coliforms (cfu/100ml) <1 <10 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1 Notes: Note 1: GTV = Groundwater Threshold Values refers to "European Communities Environmental Objectives (Groundwater) Regulations, 2010 (S.I. No. 9 of 2010)" as amended by "European Union Environmental Objectives (Groundwater)(Amendment) Regulations, 2016 (SI No. 366 of 2016)". "Threshold Values" have been established for pollutants that are causing a risk to groundwater bodies. Exceedance of a relevant threshold value at a representative monitoring point triggers further investigation to confirm whether the criteria for poor groundwater chemical status are being met.

4 Note 2: IGV = The Interim Guideline Values for Groundwater from the Environmental Protection Agency (EPA) report Towards Setting Guideline Values for the Protection of Groundwater; Interim Report (2003). Note these standards are presented for guideline purposes only, therefore, due care should be exercised in cross-referencing these standards with the groundwater results obtained Highlighted & Bold Denotes reported values exceed the relevant groundwater regulation value. ~ Denotes no groundwater assessment criteria.

5 Table 1.2: Quarterly Parameters for Private Wells, Q Parameter PW2-09 PW4 PW9 PW11 PW15 Water Quality 1 Standard MAC 2 ph (ph units) o C (µs/cm) Ammoniacal Nitrogen (as N) < Iron (µg/l) <12 <12 < Potassium < Sodium Chloride TON (as N) ~ Total Phenols (µg/l) <0.5 <0.5 <0.5 <0.5 <0.5 ~ TOC <1 < ~ Total Coliforms (cfu/100ml) Faecal Coliforms (cfu/100ml) <1 <1 <1 1 <1 0 Notes: Note 1: Water Quality Standard = Water Quality standards set in S.I. No. 278 of 2007, European Communities (Drinking water) (No.2) Regulations, Note these standards are presented for guideline purposes only and do not relate specifically to groundwater quality standards. Therefore due care should be exercised in crossreferencing these standards with the groundwater results obtained. Note 2: MAC= Maximum Admissible Concentration. Highlighted & Bold Denotes reported values exceed the relevant MAC value. ~ Denotes no groundwater assessment criteria.

6 1.4 Interpretation of Results Monthly Groundwater Elevation and Temperature Monitoring: In general the level of water in the wells has been comparable to the previous quarter. Temperature of the groundwater is also consistent with the previous quarter. No sample was available at BH4-07, BH16-07 and BH16R as groundwater levels had dropped throughout Quarter and Quarter This is likely to be due to the prolonged dry weather periods in recent months Quarterly Chemical Analysis: As previously mentioned the groundwater laboratory analytical results were compared where applicable, to the relevant standards in the Statutory Instrument S.I. No. 9 of 2010: European Communities Environmental Objectives (Groundwater) Regulations 2010, as amended 2012 (S.I. No. 149 of 2012). The Interim Guideline Values (IGVs) for Groundwater from the Environmental Protection Agency (EPA) report Towards Setting Guideline Values for the Protection of Groundwater; Interim Report (2003) were used in the absence of groundwater standards for specific parameters. A number of exceedances have been noted and are highlighted in Table 1.1. The levels of Conductivity, Ammonicial Nitrogen and Chloride were above the respective Groundwater Threshold Value (GTV) for these parameters. The GTV for Conductivity (1875 µs/cm) was exceeded at BH4-07 (3130 µs/cm) and BH9D (1304 µs/cm). The GTV for Ammonicial Nitrogen (0.175 mg/l) was exceeded at BH2 (0.39mg/l), BH3 (3.02 mg/l), BH4-07 (124 mg/l) and BH10D (0.204mg/l). The GTV for Chloride (187.5 mg/l) was exceeded at BH4-07 (268 mg/l) and BH9D (189 mg/l). All groundwater wells exceeded the IGV for Iron (200 mg/l) with the maximum value at BH2 (107,849 mg/l) and minimum value at BH13-07 (780mg/l). The IGV for Potassium (5 mg/l) was exceeded at BH4-07 (90 mg/l), BH9D (10 mg/l) and GWR1 (5mg/l). The IGV for Sodium (150 mg/l) was exceeded at BH4-07 (262 mg/l). All groundwater wells were below the IGV for Phenols (<0.5µg/l) was. The results of the remaining parameters tested at these locations remain broadly in-line with previous results, with only slight variations observed. The results for analysis of five private well samples taken in Q1 are outlined in Table 1.2. These results were compared to Water Quality Standards set in S.I No. 278 of 2007 European Communities (Drinking Water) (No.2) Regulations, It should be noted that these standards are presented for guideline purposes only and do not relate specifically to groundwater quality standards. The level of Ammoniacal Nitrogen detected at PW15 (5.53mg/l) exceeded the Maximum Admissible Concentration (MAC) value of 0.23mg/l, and Iron levels for this private well (16793µg/l) and for PW11 (784µg/l) exceed the stipulated MAC value of 200µg/l.

7 Total and Faecal coliforms were detected in samples taken from private wells PW4 and PW11, which is an exceedance of the MAC value (0cfu/100ml). It should be noted that PW4 has poor well head protection and the wells are open to surface contamination. The results of the remaining parameters tested for the private well samples remain broadly in-line with previous results, with only slight variations observed from that of the previous monitoring event; please refer to table 1.3 below.

8 Table 1.2 Groundwater Impact Interpretation, Q Well ID Parameter Exceeded Previous Quarter Parameter Exceeded Q 1, 2017 Comment Not contaminated Contaminated; Interpreted Cause: Poor Septic Landfill wellhead Tank Protection BH1 Fe & Cl Fe Adjacent to, but up gradient of unlined area of landfill - impact possibly due to leachate BH2 BH3 BH4-07 BH9D Fe Ammoniacal Nitrogen & Fe EC, Ammoniacal Nitrogen, Fe, K, Na, & Cl EC, Fe, K, Cl & Total Coliforms Ammoniacal Nitrogen & Fe Total & Faecal Coliforms Ammoniacal Nitrogen & Fe EC, Ammoniacal Nitrogen, Fe, K, Na, Cl & Total Coliforms Ammoniacal Nitrogen, Fe, K, Cl & Total Coliforms mounding and local flow reversal. Minor, unconfirmed impact. Possibly owing to the landfill? Borehole between Silliot Hill and KTK landfill Up gradient of landfill BH10D EC, Fe, Chloride & Total Coliforms Ammoniacal Nitrogen & Fe Possibly owing to the landfill? BH11D No Sampled Fe Possibly owing to the landfill? BH EC, Total Coliforms Fe Up gradient of landfill?

9 GWR 1 Fe, Chloride Fe & K Increased resolution down gradient of landfill? GWR 2 Fe & Total Coliforms Fe Increased resolution down gradient of landfill? GWR 3 Fe & Total Coliforms Fe Increased resolution down gradient of landfill? PW2-09 No exceedences No exceedences Well head at ground level PW4 Total & Faecal Coliforms PW9 Faecal Coliforms No exceedences PW11 PW15 Fe, Total & Faecal Coliforms Ammoniacal Nitrogen & Fe Total Coliforms Well head at ground level Fe, Total & Faecal Coliforms Ammoniacal Nitrogen & Fe Poor well head protection in closed pump house Shallow dug well, disused by resident because of proximity to their septic tank. Housed in open pump house, no wellhead protection; organic matter previously baled from well

10 1.5 Summary The groundwater flow direction at the site is approximately from north to south. Groundwater beneath the landfill and directly down gradient shows impact from the unlined portion of the landfill. Evidence suggests that private wells are not impacted by the landfill, but that septic tank contamination/poor wellhead protection is a more likely source. Further groundwater monitoring events will enable further continued assessment of groundwater quality at the site.

11 APPENDIX 1

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