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3.1.7 Surface Water Monitoring Surface-water sampling locations was conducted on May 7,2007, at surface-water monitoring stations ASW-1 and ASW-2. 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 2006 monitoring period at downgradient surface-water monitoring station ASW-2. 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 second quarter 2007. 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 second quarter 2007. 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 and analytical results for the second quarter 2007 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. The GTF operated for 1,888 hours between April 1 and June 30, 2007, at 86.4 percent uptime,and treated 22.266 million gallons of groundwater at an average flow rate of 197 gallons per minute, or 0.283 million gallon per day. During this period, the GTF removed approximately 3.2 pounds of VOCs(CH2M Hill, 2007). 3.2 SUMMARY Groundwater quality conditions beneath the Austin Unit during the second quarter 2007 monitoring period are generally similar to historical results. CLs were exceeded in DMP wells AMW-7,AMW-13, and AMW-14. However, none of the CL exceedances exhibited statistically significant increasing trends,while statistically significant decreasing VOC trends were calculated in well AMW-14. 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,AMW-10,and AMW-19,while decreasing VOC trends were noted in CAP wells AMW-1,AMW-11, and AMW-18.The increasing cis-1,2-DCE D:0007_0043\F0rwardAus[in sp07_doc '- 12 Geologic Associates