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FORW I-1 LANDFILL 9999 S.Austin Road Manteca,CA 95336 (209)982-4298, Fax(209)982-1009 July 30, 2012 JN: 2012-0027 Mr. Ross Atkinson Central Valley Regional Water Quality Control Board 11020 Sun Center Drive, #200 Rancho Cordova, CA 95670-6114 SUBJECT: JANUARY—JUNE 2012 FIRST SEMIANNUAL WATER QUALITY MONITORING REPORT FRENCH CAMP LANDFILL SAN JOAQUIN COUNTY, CALIFORNIA Forward, Inc. (Forward) is pleased to submit the January through June 2012 semiannual monitoring report for the French Camp Landfill, in compliance with the California Regional Water Quality Control Board - Central Valley Region(RWQCB) Waste Discharge Requirement (WDR) Order Number R5-2007-0046. This report summarizes standard observations and presents the results of surface-water, groundwater, and soil-pore gas monitoring from the semiannual (January 1 through June 30, 2012) monitoring period. Groundwater quality conditions beneath the French Camp Landfill during the monitoring period are generally similar to those observed in previous monitoring periods and no notices of violation or areas of concern were observed during the monitoring period. One or more concentration limits (CLs)were exceeded in samples collected from wells MW-6A, MW-9A, MW-913, and MW-10A. However, with the exception of the chloride concentration measured in well MW-10A, none of the constituents that exceeded an established CL exhibited a statistically significant increasing trend. In January 2005 a No Release Demonstration(NRD) for groundwater monitoring well MW-l0A was performed (Herst, 2005) in response to CL exceedances of chloride and total dissolved solids (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 trichlorofluoromethane (TCFM) were measured above the practical quantitation limit (PQL) in the samples collected from wells MW-6A and MW-9A, respectively. Confirmation sampling was not performed since chloroform and TCFM have already been confirmed in these wells. However, given the distance well MW-6A is from the landfill, the chloroform concentrations recently measured in upgradient well MW-6A are not believed to be the result of a release from the landfill. Furthermore, the TCFM concentrations measured in well MW-9A is well below risk-based concentrations and a statistically significant decreasing trend was calculated for the TCFM concentrations measured in well MW-9A. The