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3.1.7 Surface Water Monitoring Surface-water sampling was conducted at surface-water monitoring stations ASW-1 and ASW-2 on February 4, 2008. Table 3-4 summarizes the current analytical results for surface water samples collected at the Austin Unit and compares the results with the WQPS (concentration limits). No CLs were exceeded during the first quarter 2007 monitoring period at downgradient surface-water monitoring station ASW-2, and no VOCs were detected at surface water monitoring stations during the first quarter 2008 monitoring period. A comparison of upgradient(ASW-1)to downgradient (ASW-2) surface water samples indicates generally similar concentrations. 3.1.8 Leachate Monitoring According to the Operations Manager, no leachate was taken off site during the first quarter 2008. 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 2008. Leachate samples were collected from the pond on a monthly basis and analyzed in the field for pH and specific conductance. Results of monthly field monitoring measurements for the first quarter 2008 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. At the GTF, contaminated groundwater is extracted by two wells (EW-1 and EW-2),treated, and discharged to an infiltration pond. Between January 1,2008, and March 31, 2008, the GTF operated for 1,854 hours at 84.9 percent uptime. The GTF treated 22.167 million gallons of groundwater at an average flow rate of 199 gallons per minute, or 0.287 million gallons per day. During this period,the GTF removed approximately 2.0 pounds of VOCs (CH2M Hill, 2008). 3.2 SUMMARY Groundwater quality conditions beneath the Austin Unit during the first quarter 2008 monitoring period are generally similar to historical results. CLs were exceeded in DMP wells AMW-6, AMW-7,AMW-13, and -14, and with the exception of the barium concentration measured in well AMW-14 and the bicarbonate and cis-1,2-DCE concentrations measured in well AMW-13, none of the CL exceedances 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 wells AMW-1 and AMW-19,while decreasing VOC trends were noted in CAP wells AMW-10 D:\2007_0043\FA_1 QOB.doc 12 Geologic Associates