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presented in Appendix D. Based on a comparison of the data obtained during the fourth <br /> quarter 2007 monitoring period, the following analytes were found to exceed a CL: <br /> CONSTITUENT Concentration DMP Monitoring Wells <br /> Limit MW-6A* MW-7A* MW-8A MW-9A MW-9B MW-10A <br /> GENERAL CHEMISTRY(mg/l,except as noted) <br /> Calcium 138.1 180 180 <br /> hlolide 269.1 550 470 <br /> a nesiuin 75 88 100 <br /> H 6.569-8.053 6.19 6.24 <br /> otassium 2.172 2.2 2.6 4.8 3.3 <br /> otal Dissolved Solids(TDS) 1600 1800 <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 Specific Conductance, Sulfate,TDS <br /> MW-8A None Apparent _ Nitrate-N <br /> MW-9A None A arent None Apparent <br /> MW-9B Sulfate None Apparent <br /> MW-10A Chloride,Potassium,Specific Nitrate-N <br /> Conductance <br /> As shown above, CLs were exceeded for inorganic constituents in the samples collected <br /> from wells MW-8A, MW-9A, MW-913 and MW-10A. For the constituents that exceeded <br /> a CL, only concentrations of chloride and potassium measured in the sample collected <br /> from well MW-l0A exhibited a statistically significant increasing trend during the fourth <br /> quarter 2007 monitoring period. In response to statistical exceedances of chloride and <br /> TDS identified in samples from well MW-l0A during the second quarter 2004, a No <br /> Release Demonstration (NRD) for groundwater monitoring well MW-l0A was <br /> performed (GLA, 2003). The NRD concluded that French Camp Landfill, located within <br /> the central Stockton area, has been impacted by saltwater intrusion and the elevated <br /> chloride and potassium concentrations measured in well MW-l0A are believed to be the <br /> result of this condition and not the result of landfill-related impacts. <br /> 4.5 LEACHATE MONITORING <br /> The laboratory results for leachate monitoring well MW-2, are summarized in Table 3 <br /> and time-series concentration plots are presented in Appendix D. As shown on Table 3, <br /> no VOCs were measured in leachate monitoring well MW-2 during the fourth quarter <br /> 2007 monitoring period. <br /> D:\2003_021\FC_4Q07.doc <br /> 4 Geologic Associates <br />