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Groundwater quality conditions beneath the French Camp Landfill during the 2013 monitoring year are generally similar to those observed over the previous years. During one or both semiannual monitoring events in 2013, CLs were exceeded for chloride at wells MW-9B and MW-10A; and for pH (lower limit), specific conductance, and TDS at well MW-10A. However, no statistically significant increasing trends were calculated for constituents exceeding a CL. With the exception of the consistent detection of TCFM at well MW-9A and chloroform at well MW-6A,no VOCs were detected above a PQL in groundwater samples collected during the 2013 monitoring year. During the first semiannual 2013 monitoring period, all groundwater, leachate, and surface water sample points analyzed for the five-year constituents of concern (CDCs). With respect to organic COCl, one semi-VOC (dimethyl phthalate) was detected in samples from wells MW-2,MW-6A, and MW-10A. Additionally,2,4-D was detected in all surface water samples and dimethoate was detected in upstream surface water samples. When detected, concentrations of organic COCs were comparable between upgradient/upstream and downgradient/downstream samples. Accordingly, the presence of these insecticides and herbicides are believed to be related to agricultural activities upgradient of the site. Inorganic COCs were generally measured at similar concentrations in both upgradient/upstream and downgradient/downstream samples. However, while cyanide was not detected in upstream surface water sample, it was measured above the PQL in the sample from downstream surface water station SW-3. Accordingly, surface water location SW-3 was retested for cyanide(Table 4)during the August 2013 sampling event. Cyanide was not detected in the retest sample. Based on the results of the COC analyses, no changes to the current monitoring program are recommended at this time. 6.3 SURFACE WATER Surface water elevations at the stream gauging stations varied by approximately two feet during the 2013 monitoring year. These changes reflect seasonal 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 2013 monitoring year are generally similar to those observed during previous monitoring years and no VOCs were detected above a PQL during the monitoring year. 6.4 SOIL-PORE GAS Pursuant to M&RP Order No. R5-2007-0046, soil-pore gas probes are monitored semiannually using a field screening protocol. During the 2013 monitoring year, methane was not detected at any of the French Camp Landfill soil-pore gas probes. is CA2013.002MC 2SA13.dm 6 Geo-Logic Associates