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® 5.5 LEACHATE MONITORING The laboratory results for leachate monitoring wells MW-IA and MW-2, constructed through waste, are summarized in Table 3 and time-series concentration plots are presented in Appendix D. As shown on Table 3,no VOCs were measured in leachate monitoring well MW-2 during the third quarter 2006 monitoring period. As discussed in section 5.1,leachate monitoring well MW-IA was reported dry as a result of the casing being extended but not the dedicated pump. Forward has extended the pump's tubing in well MW-IA which will be sampled in November during the fourth quarter 2006 sampling event. 5.6 SURFACE-WATER MONITORING Third quarter 2006 field and laboratory results for surface-water monitoring stations (SW-1, SW-2, and SW-3) are summarized in Table 4. Locations SW-1 and SW-2 are located upstream of the landfill within the Walker and French Camp Sloughs, respectively, and are used as background sampling points, while SW-3 is located downstream of the landfill at the confluence of the two sloughs. Water quality data from surface-water sampling stations were graphed on time-series concentration plots and are presented in Appendix D. As shown in thetime-series plots, the general chemistry and metals constituents are generally consistent with historical concentrations. Organic results indicate that trace level concentration of dibromochloromethane were measured in ® the samples collected from surface water stations SW-1 and SW-2. As discussed in section 5.2, dibromochloromethane is a confirmed laboratory contaminant. For the surface water monitoring stations at the French Camp Landfill, CLs are used for the WQ�PS. The CLs shown in Table 4 were calculated by Herst&Associates using Sanitas , a state-approved statistical software program using historical data from background surface water stations SW-1 and SW-2, and are presented in Appendix D. As shown in Table 4, CLs for pH were exceeded at surface water stations SW-1 and SW-3 and the pH in the sample from surface water station SW-2 was below the lower CL during the third quarter 2006 monitoring period. Trend analyses indicate that turbidity at surface water stations SW-1, SW-2, and S -3 depict statistically significant increasing trends. Given that 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. 6.0 SUMMARY Groundwater quality conditions beneath the French Camp Landfill during the third quarter 2006 monitoring period are generally similar to those observed in previous monitoring periods. One or more inorganic CLs were exceeded in DMP wells MW-6A, MW-9A, MW-9B, and MW-10A. However,no statistically significant increasing trends were noted for constituent concentrations exceeding a CL. In addition,bromoform was ® detected above the PQL in background well -6A and TCFM was detected above the DA2003_021\FC_sam06.doc 5 Geologic Associates