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MW-6A. However, a similar, slightly higher concentration of chloroform was detected in the QA/QC field blank suggesting inadvertent field or laboratory contamination. During the second semiannual 2010 monitoring period, an estimated trace level concentration of TCFM was measured in well MW-9A at the method detection limit. 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 2010 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 2010 monitoring year, only turbidity concentrations in all three surface-water stations have consistently exhibited increasing trends. 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 downgradient surface- water station SW-3 is considered reflective of regional conditions and not facility related. In fact,turbidity concentrations are significantly lower in the downstream sample SW-3. During the first semiannual 2010 monitoring period,trace level concentrations of toluene were detected in all three surface-water stations. It should be noted however, toluene is a common field/laboratory contaminant and that no VOCs were detected in surface water samples collected during the second semiannual 2010 monitoring event. 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 2010 monitoring year,no methane was detected in any of the soil-pore gas probes. 6.5 COMPLIANCE RECORD During the 2010 monitoring year,no NOVs were issued by the LEA or CIWMB and the site is currently in compliance. 7.0 SUMMARY Groundwater quality conditions beneath the French Camp Landfill during the monitoring period are generally similar to those observed in previous monitoring periods. CLs were exceeded for four inorganic constituents in the samples collected from well MW-10A, and with the exception of the chloride concentration measured in the sample collected D:\201M030\FC_2SA10.doc 7