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sample indicate that there were no new COCs detected above the PQL, and as a result, verification testing is not required. 2.1.7 Surface Water Monitoring Site run-on and run-off control facilities are designed to effectively channel surface water to site stormwater/sedimentation ponds. According to the Operations Manager, there were no discharges to surface water during the reporting quarter. During the fourth quarter 2010 monitoring period, surface-water monitoring stations FSW-I and FSW-2 were sampled on December 27, 2010. Table 2-7 summarizes the current analytical results for surface water samples collected at the Forward Unit. As shown on Table 2-7, no VOCs were detected in the samples collected from the surface water stations during the fourth quarter 2010 monitoring period. A comparison of upgradient(FSW-2)to downgradient(FSW-1) surface water samples indicates generally similar concentrations suggesting that the landfill operations are not impacting surface water quality. 2.2 SUMMARY Groundwater quality conditions beneath the Forward Unit during the fourth quarter 2010 monitoring period are generally similar to those observed in previous monitoring periods. During the fourth quarter 2010 monitoring period, 17 new historical intrawell maximum values were measured in samples collected from groundwater monitoring wells, including eight first-time VOC detections. The organic results for the Forward Unit indicate that the following VOCs were measured above their respective PQLs, acetone and MEK in the samples collected from upgradient(background)wells MW-2A and MW-17; and cis-1,2-DCE, PCE, and TCE in the samples collected from wells MW-22 and MW-23R. In addition, PCE was measured at an estimated trace concentration in the sample collected from well MW-14. CLs were exceeded for one or more monitoring parameters in samples from seven wells. In accordance with the RPCMP, inorganic exceedances of CLs that are potential impact constituents (potassium at well MW-18, and chloride at well MW-22) will be resampled in February 2011 (during the first quarter 2011 sampling event), and a second independent sample will be collected in March 2011. The results of the two retests will be submitted to DTSC and RWQCB under separate cover. The fourth quarter 2010 leachate monitoring results are generally similar to those observed historically. During the monitoring period, 13 dissolved metal constituents were measured with eight above their PQL; three VOCs were measured above their PQL; eight semi-volatile organic compounds(SVOCs) were measured with three above their PQL; and one herbicide was measured above its PQL in the leachate sample collected during the fourth quarter 2010 monitoring period. No pesticides were detected in the leachate sample. The results of the annual leachate sample indicate that there were no new COCl detected. During the October and November 2010 inspections,the CEHD measured methane concentrations exceeded the regulatory limit of five percent in perimeter soil-pore gas D:X2010_0013TA_4Q10.doc 8 Geologic Associates