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7.0 SUMMARY During the monitoring period, groundwater quality conditions beneath the French Camp Landfill are generally similar to those observed in previous monitoring periods. Inorganic CLs were exceeded for chloride in the sample from well MW-913; and for pH in the sample from well MW-10A. However, none of the constituents that exceeded a CL exhibited a statistically significant increasing trend. In January 2005 a No Release Demonstration(NRD)for groundwater monitoring well MW-IOA 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 TDS 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 background well MW-6A and compliance well 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 has been attributed to LFG. Results of trend analysis performed on these constituents indicate no statistically significant increasing trends. The results of water quality analyses completed from the surface water monitoring stations are generally consistent with previous results. With the exception of a trace detection of toluene at upstream surface water monitoring station SW-1, no VOCs were detected during the monitoring period. A comparison of upstream (SW-1 and SW-2)to downstream(SW-3)surface water samples indicates generally similar inorganic constituent concentrations between upstream and downstream surface water monitoring locations, suggesting that the landfill is not impacting surface water quality. 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. As required every five years, samples collected during the current monitoring period from all groundwater and leachate monitoring wells and surface water monitoring stations were analyzed for the COCs listed in RWQCB Order No. R5-2007-0046. With respect to organic COCs, one SVOC (dimethyl phthalate)was detected in samples from wells MW-2,MW-6A, and MW-10A. Additionally, 2,4-D was detected in all surface water samples and dimethoate was detected in upstream surface water samples. When detected, concentrations of organic COCs were comparable between upgradient/upstream and downgradient/downstream samples. Accordingly, the presence of these insecticides and herbicides are believed to be related to agricultural activities upgradient of the site. Inorganic COCs were generally measured at similar concentrations in both upgradient/upstream and downgradient/downstream samples. However,cyanide was not CA2013-0023\FC tSA13.doc 6 Geo-Logic Associates