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6.0 SUMMARY During the monitoring period, groundwater quality conditions beneath the French Camp Landfill are generally similar to those observed in previous monitoring periods. One or more CLs were exceeded in samples collected from wells MW-6A, MW-9A, MW-9B, and MW-10A. However, with the exception of the chloride concentration measured in well MW-10A, none of the constituents that exceeded a WDR established CL exhibited a statistically significant increasing trend. In January 2005 a No Release Demonstration (NRD) for groundwater monitoring well MW-l0A was performed (Herst, 2005) in response to CL exceedances of chloride and TDS. The NRD concluded that French Camp Landfill, located within the central Stockton area, has been impacted by saltwater intrusion and the elevated chloride and TD concentrations measured in well MW-l0A are believed to be the result of this condition and not the result of landfill-related impacts. During the monitoring period, chloroform and TCFM were measured above the PQL in the samples collected from wells MW-6A and MW-9A, respectively. Confirmation sampling was not performed since chloroform and TCFM have already been confirmed in these wells. However, given the distance of well MW-6A from the landfill,the chloroform concentrations recently measured in well MW-6A are not believed to be the result of a release from the landfill. The TCFM concentrations measured in well MW-9A is well below risk-based concentrations and a statistically significant decreasing trend was calculated for the TCFM concentrations measured in well MW-9A. Field screening results from soil-pore gas monitoring probes indicate that no methane was measured in soil-pore gas monitoring probes during the monitoring period. The results of water quality analyses completed from the surface-water monitoring stations are generally consistent with previous results. No VOCs were detected in the samples collected from the surface-water stations during the monitoring period. A comparison of upgradient(SW-1 and SW-2)to downgradient (SW-3) surface-water samples indicates generally similar inorganic constituent concentrations in the upgradient and downgradient surface water station, suggesting that the landfill is not impacting surface water quality. During the current monitoring period, no CL were exceeded, and with the exception of carbonate at surface-water stations SW-1 and SW-3, and turbidity at surface-water station SW-1,no statistically significant increasing trends were noted. Given that statistically significant increasing trends were both noted at background surface-water point SW-1, these increasing trends are not believed to be the result of an impact from the landfill. C:\2012-00nFC 15Al2.doc 6 Geo-Logic Associates