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on Table 3-5, no VOCs were detected in the surface water samples collected during the monitoring period. A comparison of upgradient (ASW -1) to downgradient (ASW -2) surface water samples indicates generally similar inorganic constituent concentrations suggesting that the landfill operation are not impacting surface water quality. 3.1.8 Leachate Monitoring According to the Operations Manager, no leachate was taken off site during the third quarter 2011. 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 third quarter 2011. Leachate samples were collected from the pond on a monthly basis and analyzed in the field for pH, specific conductance, and temperature. 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 five wells (EW -1, EW -2, EW -3, EW -3R, and EW -4), treated, and discharged to an infiltration pond. During the monitoring period, the GTF treated 18,268,800 gallons of groundwater at an average flow rate of 172 gallons per minute, or 247,182 gallons per day. During the monitoring period, it is calculated that the GTF removed approximately 1.42 pounds of VOCs. Groundwater quality conditions beneath the Austin Unit during the third quarter 2011 monitoring period were generally similar to historical results. CLs were exceeded in DMP wells AMW-6, AMW-12, 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, statistically significant increasing trends were noted for one or more VOC constituents in CAP wells AMW-1, AMW-10, AMW-19, and AMW-1913R, while one or more decreasing VOC trends were noted in CAP wells AMW-1, AMW-4, AMW-5/5R, AMW-10, and AMW-11. The increasing cis-1,2-DCE trends in wells AMW-1 and AMW-10, suggest that active reductive dechlorination is occurring in the vicinity of these wells. C:\2011-0050\FA 3Qll.docx 12 Geo -Logic Associates