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Water quality Monitoring Report French Camp Landfill In order to evaluate changes in water quality in DMP wells at the French Camp Landfill, Sen's Slope trend analyses were performed for those constituents exceeding a CL. During the monitoring period, no statistically significant increasing temporal trends were calculated for constituents exceeding a CL and current concentrations measured in these wells are generally within the historical range of values for these wells. Trend analyses are presented in Appendix D. 4.5 Leachate Monitoring The laboratory results for leachate monitoring well MW-2 are summarized in Table 3. As shown on Table 3, no VOCs were detected in leachate monitoring well MW-2 during the monitoring period. 4.6 Surface Water Monitoring Field and laboratory results for surface water monitoring stations(SW-1,SW-2, and SW-3) for the current monitoring period are summarized in Table 4 and time-series concentration plots are presented in Appendix D. Stations 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. Station SW-3 is located downstream of the landfill at the confluence of the two sloughs. A comparison of upgradient (SW-1 and SW-2) to downgradient (SW-3) surface water samples indicates generally similar inorganic constituent concentrations. Trace concentrations of chloroform were measured in upstream samples and low, quantifiable concentrations of bromodichloromethane and chloroform and a trace concentration of dibromochloromethane were measured in the downstream sample. These particular VOCs are drinking water disinfection byproducts (trihalomethanes) that likely originate from a source other than the landfill. No other VOCs were detected in the surface water monitoring stations. In a letter dated June 23, 2014, the RWQCB was notified of the non-statistical exceedance in SW-3 and confirmation samples were collected in June 2014. Stream gauging was performed on February 24 and May 5, 2014, at monitoring points SG-1 and SG-2 and the data is summarized in Table S. As shown in Figures 1 and 2, monitoring point SG-1 is located upgradient in the Walker Slough and monitoring point SG-2 is located upgradient,in the French Camp Slough. 5.0 SOIL-PORE GAS MONITORING In accordance with WDR Order No. 115-2007-0046, soil-pore gas probes are monitored semiannually using a field screening protocol, and soil-pore gas samples are only collected if field screening indicates methane concentrations greater than 2.5 percent. During the monitoring period, field screening of soil-pore gas probes was conducted on M:\2014.0012\FC i5A14.doc 5 7/10/2014,Rev.0