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surface water samples collected at the Austin Unit and compares the results with the WQPS (concentration limits). During the first quarter 2010 monitoring event, no CLs were exceeded at surface water monitoring points,while toluene was detected at a trace concentration in the sample collected from downgradient surface water station ASW-2. It should be noted, however, that toluene is a suspected field/laboratory contaminant since similar concentrations were measured in QA/QC blanks. A comparison of upgradient(ASW-1) and downgradient(ASW-2) surface water samples indicates generally similar inorganic constituent concentrations, suggesting that landfill operations are not impacting surface water quality. 3.1.8 Leachate Monitoring According to the Operations Manager, no leachate was taken off site during the first quarter 2010. The leachate collection system, which collects leachate from the north face of the landfill,has been operational since November 1996. WQPS (concentration limits) are not required for leachate because it is collected and removed for disposal,rather than discharged. According to the Operations Manager, the LCRS operated effectively during the first quarter 2010. Leachate samples were collected from the pond on a monthly basis and analyzed in the field for pH and specific conductance. The results of monthly field monitoring measurements are presented in Table 3-6. 3.1.9 Groundwater Treatment Facility Operations The Groundwater Treatment Facility(GTF) at the Austin Unit has been operational since 1994 to mitigate impacts from landfill releases. Currently, impacted groundwater is extracted from four wells (EW-1, EW-2, EW-3R, and EW-4),treated, and discharged to an infiltration pond. During the monitoring period, the GTF operated continuously and treated 20,658,900 gallons of groundwater at an average flow rate of 159 gallons per minute, or 228,975 gallons per day. During the monitoring period, it is calculated that the GTF removed approximately 2.55 pounds of VOCs. 3.2 SUMMARY Groundwater quality conditions beneath the Austin Unit during the first quarter 2010 monitoring period were generally similar to historical results. CLs were exceeded in DMP wells AMW-13 and AMW-14, however,with the exception of the barium concentration measured in well AMW-14, no CLs were exceeded for constituents that exhibited statistically significant increasing trends. In the CAP wells,trend analyses are performed instead of comparison to CLs. During the current monitoring period, one or more statistically significant increasing trends were noted for VOC constituents in CAP wells AMW-1, AMW-10, AMW-19, and AMW-I 9BR, while one or more decreasing VOC trends were noted in CAP wells AMW-1, AMW-10, and AMW-11. The increasing vinyl chloride and/or cis-1,2-DCE trends in wells AMW-I and AMW-10 suggest that active reductive dechlorination is occurring in the vicinity of these wells. D:\2010_0013\FA_1 Q1 O.doc 13 Geologic Associates