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the CDCs included for the French Camp Landfill and Tables 2 through 4 summarize the results. Excluding the metals, which may be naturally occurring,no COCl were detected in samples collected from the French Camp Landfill during the monitoring period. As shown on Tables 2 through 4, the following metal analytes exceeded state or federal maximum contaminant levels (MCLs); arsenic in well MW-6A; iron in wells MW-7A, MW-913, MW-10A; and manganese in wells MW-2,MW-7A, MW-8A, MW-913, and MW-I OA. For surface water, the following metal analytes exceeded state or federal MCLS; iron at stations S -1, SW-2, and SW-3; and manganese at station SW-1. Given the fact that elevated arsenic, iron, and manganese concentrations were measured in background wells and upgradient surface water stations, the MCL exceedances do not appear to be related to a release from the landfill. 5.0 SOIL-PORE GAS MONITORING In accordance with WDR Order No. R5-2007-0046, soil-pore gas probes are monitored semiannually using a field screening protocol, and soil-pore gas samples are only collected if field screening indicates methane concentrations greater than 2.5 percent. During the monitoring period, field screening of soil-pore gas probes was conducted on August 18, 2009. As shown on Table 6,no methane was detected in any of the soil-pore gas probes, and as a result, no samples were collected. 6.0 ANNUAL SUMMARY 6.1 GENERAL During the 2009 monitoring year, groundwater elevation measurements were performed quarterly and water quality monitoring points and soil-pore gas probes were sampled semiannually in accordance with WDR Order No. R5-2007-0046. All of the monitoring points are sampled for the monitoring parameters summarized in Table 1. Time-series plots depicting groundwater and surface water constituent concentrations and a tabular summary of the historical monitoring are presented in Appendix D and an electronic format is included in Appendix C. Piper diagrams of the semiannual data obtained in 2009 are included in Appendix D, and hydrographs of the detection monitoring wells, illustrating historic groundwater elevations,well screen elevations, and pump intake elevations are also included in Appendix D. Discussions of the historical trends in constituent concentrations are presented in Section 4. 6.2 GROUNDWATER Groundwater elevations have remained relatively static over the past year,reflecting seasonal precipitation patterns. Groundwater generally flows to the south across the site at a gradient of 0.002 to 0.003 ft/ft. D:\200&0012\FC_2SA09.doc 6 Geologic Associates