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plots, general chemistry and metals constituent concentrations are generally consistent <br /> with historical concentrations. However, constituent concentrations of bicarbonate, <br /> calcium, magnesium, and sodium measured in the samples collected from well MW-9A <br /> and/or MW-l0A have exhibited decreasing concentrations outside of their historical <br /> range of values during the 2010 monitoring year. <br /> With the exception of one estimated trace level concentration of trichlorofluoromethane <br /> (TCFM) in the sample collected from well MW-9A, no VOCs were detected in any of the <br /> groundwater monitoring wells during the monitoring period. <br /> Concentration Limits <br /> For DMP monitoring wells at the French Camp Landfill,concentration limits (CLs) <br /> provided in the WDRs are used for the water quality protection standards (WQPS). <br /> Based on a comparison of the data obtained during the current monitoring period, the <br /> following analytes were found to exceed a CL: <br /> CONSTITUENT Concentration I DMP Monitoring Wells <br /> Limit MW-6A*I MW-7A*I MW-8A I MW-9A I MW-9B I MW-10A <br /> GENERAL CHEMISTRY(mgA) <br /> Chloride 249 627 <br /> ecific Conductance umhos/cm 2500 3077 <br /> H 6.9-10.21 6.89 <br /> otal Dissolved Solids(TDS) 1600 1800 <br /> NOTES: (*)—Background Well. <br /> Trend Analysts <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 Calcium,Magnesium,pH <br /> MW-7A Potassium Chloride, Specific Conductance, Sulfate,TDS <br /> MW-8A None Apparent Bicarbonate,Ma esium,Nitrate-N,TDS <br /> MW-9A None Apparent None Apparent <br /> MW-9B Potassium,Sulfate pH <br /> MW-10A Chloride,Specific Conductance Nitrate-N <br /> As presented above, CLs were exceeded for several constituents in the sample collected <br /> from well MW-10A,but with the exception of chloride,none of the constituents that <br /> exceeded a WDR established CL exhibited a statistically significant increasing trend <br /> during the monitoring period. As shown in the time-series plots (Appendix D), <br /> concentrations of chloride measured in well MW-10A during the monitoring period(627 <br /> mg/L) are within the historical range of values since 2002. In January 2005 a No Release <br /> Demonstration(NRD) for groundwater monitoring well MW-l0A was performed(Herst, <br /> 2005) in response to CL exceedances of chloride and TDS. The NRD concluded that <br /> v:2030-W30\Fc zsAlo.doc <br /> 4 <br />