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result of landfill-related impacts. Since specific conductance and TDS values often mimic each other, the specific conductance exceedance is believed to the result of this same condition. 5.5 LEACHATE MONITORING The laboratory results for leachate monitoring wells MW-lA 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, 11 VOCs were measured above the practical quantitation limit(PQL) in leachate monitoring well MW-lA during the first quarter 20006 monitoring period, while no VOCs were detected in leachate monitoring ' well MW-2. 5.6 SURFACE-WATER MONITORING First 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. For the surface water monitoring stations at the French Camp Landfill, CLs are used for theQ�PS. The CLs shown in Table 4 were calculated by erst Associates using Sanitas , a state-approved statistical software program using historical data from background surface water stations S -1 and S -2, and are presented in Appendix D. As shown in Table 4, CL exceedances were only noted for the barium concentrations in the samples from stations SW-2 and SW-3;however, no increasing trends were noted for barium at either surface-water station. Trend analyses indicate that only turbidity at surface water stations SW-1, SW-2, and SW-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 first quarter 2006 monitoring period are generally similar to those observed in previous monitoring periods. During the first quarter 2006 monitorineriod, one or more inorganic CLs were exceeded in DMP wells MW-8A, MW-9A,-M-W-9B, and MW-10A. In addition, organic constituent results indicate that a low-level concentration of 1,2-DCA was ' measured in the sample collected from well MW-9B. With the exception of the chloride and specific conductance concentrations measured in the sample collected from well MW-10A,no statistically significant increasing trends were noted for constituent concentrations exceeding a CL. Previous statistical DA2003_021TC_w06.doc 5 Geologic Associates