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March 16, 2010. 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 SUMMARY Groundwater quality conditions beneath the French Camp Landfill during the monitoring period are generally similar to those observed in previous monitoring periods. CLs were exceeded for a constituent in the samples collected from background well MW-6A, and compliance wells MW-9A and MW-913. It should be noted, however, that none of the constituents that exceeded a CL exhibited a statistically significant increasing trend during the monitoring period. Previous statistical exceedances for chloride and TDS have been identified in samples from well MW-l0A and a NRD for groundwater monitoring well MW-l0A (Herst, 2005) concluded that the French Camp Landfill 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 chloroform was measured above the PQL in the sample collected from wells MW-6A. However, a similar concentration of chloroform was also detected in the QA/QC field blank. The presence of chloroform in well MW-6A is not believed to the result of a release from the landfill since chloroform has been rarely detected in on-site wells and background well MW-6A is located approximately 1200 feet cross-gradient from the landfill. The results of water quality analyses completed for surface-water monitoring stations are generally consistent with previous results. During the monitoring period, trace level concentrations of toluene were detected in all three surface water stations. It should be noted, however, that toluene is a common field/laboratory contaminant. With the exception of turbidity in all three surface-water samples, no statistically significant increasing trends were noted. Since turbidity exhibits a statistically significant increasing trend at background surface water stations SW-1 and SW-2, the increasing trend in turbidity at SW-3 is unlikely to be indicative of an impact from the facility. The field screening results from soil-pore gas monitoring probes indicates that no methane was measured in soil-pore gas monitoring probes during the monitoring period. D:X2010-0030TC_1 SA l0.doc 6 Geologic Associates