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3.1.7 Surface Water Monitoring During the first quarter 2011 monitoring period, surface-water monitoring stations ASW-1 and ASW-2 were sampled on February 24, 2011. Table 3-5 summarizes the current analytical results of surface water samples collected at the Austin Unit. As shown 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 first 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 first 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 four wells (EW-1, EW-2, EW-3R,and EW-4),treated, and discharged to an infiltration pond. During the monitoring period, the GTF treated 19,979,378 gallons of groundwater at an average flow rate of 150 gallons per minute,or 216,221 gallons per day. During the monitoring period, it is calculated that the GTF removed approximately 2.72 pounds of VOCs. 3.2 SUMMARY Groundwater quality conditions beneath the Austin Unit during the first quarter 2011 monitoring period were generally similar to historical results. CLs were exceeded in DMP wells AMW-7, 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-I 9BR,while one or more decreasing VOC trends were noted in CAP wells AMW-1,AMW-4, ®:2011 0050\FA_iQi I.docx 12 Geologic Associates