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Groundwater quality conditions beneath the French Camp Landfill during the 2009 monitoring year are generally similar to those observed in the previous monitoring year. Excluding field parameters, CLs were generally exceeded in wells MW-9B and MW-1 OA during the monitoring year, and pH values were generally exceeded (measured below the lower CL) in all wells except background well MW-7A. Furthermore, statistically significant increasing trends were consistently noted for chloride in well MW-10A; sulfate in well MW-9B; and for bicarbonate in well MW-7A. Decreasing trends were consistently noted for pH in wells MW-6A and MW-9B; chloride, specific conductance, sulfate, and TDS in well MW-7A; calcium, magnesium, nitrate as nitrogen, and sodium in well MW-7B, and nitrate as nitrogen in well MW-10A. During the first semiannual 2009 monitoring period, a low level concentration of chloroform was detected above the PQL in the sample collected from background well MW-6A. Retest samples were collected from this well on June 30, 2009 confirmed the presence of chloroform at concentrations above the PQL. Review of the historical database indicates that since 1995 chloroform has only been detected three times at three different sample points in on-site wells, while low levels of chloroform have been intermittently detected in background well MW-6A. Since chloroform is also a constituent used to treat drinking water and has been rarely detected in on-site wells, and given the fact that background well MW-6A is located approximately 1200 feet cross- gradient from the landfill and was completed in a traffic box in a residential street, the detection of chloroform in background well MW-6A is not believed to the result of a release from the landfill. No VOCs were detected in samples from leachate monitoring well MW-2 during the 2009 monitoring year. 6.3 SURFACE WATER Surface water elevations at the stream gauging stations have remained relatively static over the past year, generally reflecting precipitation patterns. Surface water generally flows west toward the San Francisco Bay. Water quality conditions for surface water at the French Camp Landfill during the 2009 monitoring year are generally similar to those observed in the previous monitoring years. A comparison of upgradient (SW-1 and SW-2) to downgradient (SW-3) surface water samples indicates generally similar inorganic constituent concentrations in the upgradient and downgradient surface water stations, suggesting that the landfill is not impacting surface water quality. During the 2009 monitoring year, only turbidity concentrations in all three surface water stations have exhibited an increasing trend. However, given the fact that increasing trends for turbidity were calculated for upgradient surface water stations SW-1 and SW-2, the increasing trend in turbidity at surface water station SW-3 is considered reflective of regional conditions and/or are non-facility related. During the first semiannual 2009 monitoring period, carbon disulfide was measured above the PQL in the sample collected from surface water station SW-1. However, retest D:\2008-0012\FC_2SA09.doc 7 Geologic Associates