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6.0 SUMMARY Groundwater quality conditions beneath the French Camp Landfill during the third quarter 2007 monitoring period are generally similar to those observed in previous monitoring periods. During the third quarter 2007 monitoring period, inorganic CLs were exceeded in DMP wells MW-6A, MW-9A, W-913, and MW-10A, and with the exception of the chloride concentration measured in well MW-l OA,none of the constituents that exceeded a CL exhibited a significant increasing trend during the third quarter 2007 monitoring period. Previously, a NRD concluded that French Camp Landfill, located within the central Stockton area,has been impacted by saltwater intrusion and the elevated chloride and TDS concentrations measured in well MW-l0A are believed to be the result of this condition and not the result of landfill-related impacts. Organic constituent results indicate the TCFM concentration was measured above the PQL in the sample collected from well MW-9A, and 1,2-DCE was measured at a trace concentration in the sample collected from well -9 B. The low level detections of TCFM in well MW-9A are believed to be related to the recently constructed final cover system and an associated increase in LFG generation. In a meeting with the RWQCB on March 9,2007, Forward proposed quarterly monitoring of existing groundwater monitoring wells and soil-pore gas probes through May 2008 to evaluate the significance of landfill gas at the site. The results of water quality analyses completed for leachate monitoring well MW-2 indicates that no VOCs were detected in the sample from this well during the current monitoring period. The results of water quality analyses completed for surface-water monitoring stations are generally consistent with previous results. Toluene was detected at a trace concentration in the sample collected from background station SW-1. Trend analyses indicate that turbidity at surface water stations SW-1, SW-2, and SW-3 depict statistically significant increasing trends. Since turbidity exhibits a statistically significant increasing trend at background surface water stations SW-1 and S -2, the increasing trend in turbidity at SW-3 is unlikely to be indicative of an impact from the facility. A total of 17 VOCs were detected in the samples from soil-pore gas monitoring probes during the current monitoring period, with the sample from probe SGP-2A containing the highest total concentration of VOCs. No methane was detected in soil-pore gas monitoring probes during the current monitoring period. D:U007-00 TC mm07.doe 6 Geologic Associates