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samples were collected from this well in December 17,2008. The results of the retest <br /> samples indicate that no VOCs were detected and the concentration of chloroform in the <br /> primary sample was a false positive. <br /> Concentration Limits <br /> For DMP monitoring wells at the French Camp Landfill, concentration limits (CLs) are <br /> used for the water quality protection standards(WQPS). The CLs shown in Table 2 were <br /> calculated by Herst &Associates using Sanitas®, a state-approved statistical software <br /> program, and are presented in Appendix D. Based on a comparison of the data obtained <br /> during the current monitoring period, the following analytes were found to exceed a CL: <br /> CONSTITUENT Concentration I DMP Monitoring Wells <br /> Limit IMW-6A-I MW-7A-I MW-8A I MW-9A I MW-9B—FMW-IOA <br /> GENERAL CHEMISTRY(mg/1) <br /> Calcium 126.1 150 160 <br /> Chloride 249 510 430 <br /> Magnesium 75 90 <br /> pH 6.9-10.21 6.70 6.85 6.48 6.88 6.33 <br /> Potassium 2.16 4.0 <br /> Total Dissolved Solids(TDS) 1600 1700 <br /> Volatile Organic Compounds(jag/1) <br /> Chloroform 0.5 0.81 <br /> [Trichlorofluoromethane 0.5 0.61 <br /> NOTES: (*)–Background Well. <br /> Trend Analysis <br /> In order to evaluate changes in water quality in DMP wells at the French Camp Landfill, <br /> historical groundwater data were evaluated using Sen's Slope trend analyses to determine <br /> if significant increasing or decreasing trends were evident. Trend analyses, performed by <br /> Herst& Associates, are presented in Appendix D and summarized below. <br /> Well Number Increasing Trends Decreasing Trends <br /> MW-6A None Apparent pH <br /> MW-7A Bicarbonate Chloride,Specific Conductance,Sulfate,TDS <br /> MW-8A None Apparent Magnesium,Nitrate-N, Sodium <br /> MW-9A None Apparent None Apparent <br /> MW-9B Sulfate pH <br /> MW-10A Chloride Nitrate-N <br /> As shown above, CLs were exceeded for one or more constituents in the samples <br /> collected from wells MW-6A, MW-9A, MW-913, and MW-1 OA. Of note, with the <br /> exception of the chloride concentration measured in the sample collected from well <br /> MW-10A, none of the constituents that exceeded a CL exhibited a statistically significant <br /> increasing trend during the monitoring period. As shown in the time-series plots <br /> (Appendix D), concentrations of chloride measured in well MW-I OA(43 0 mg/L) are <br /> generally similar to concentrations observed in this well since May 2001. In January <br /> 2005 a No Release Demonstration (NRD) for groundwater monitoring well MW-I OA <br /> was performed (Herst, 2005)in response to CL exceedances of chloride and TDS. The <br /> D:\2008-0012\FC_25A08.doc 4 Geologic Associates <br />