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Evaluation prepared by Herst&Associates (2005),no CAP wells have exceeded the site's threshold limits. 3.1.6 Domestic Well Monitoring Two domestic wells (7898-A and 8106-A)were sampled on May 23,2006. Table 3-3 summarizes the current analytical results for the domestic well samples collected. As shown on Table 3-3,three VOCs(DCDFM,PCE, and TCE)were measured above the PQL in the samples from domestic wells 7898-A and 8106-A. In addition,two VOCs (1,1-DCA and cis-1,2-DCE)were measured at estimated trace levels in the samples from these domestic wells. 3.1.7 Surface-Water Monitoring Surface-water sampling locations was conducted on May 23, 2006, at upstream 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). With the exception of the field specific conductance,no CLs were exceeded during the second quarter 2006 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 second quarter 2006. 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 leachate monitoring and collection system operated effectively during the second quarter 2006. Leachate samples were collected on a monthly basis and analyzed in the field for pH and specific conductance. In addition to monthly monitoring, the leachate is sampled annually during the fourth quarter monitoring period for the parameters listed in Table 2-1. Results of monthly field monitoring measurements for the second quarter 2006 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 Groundwater Treatment Facility(GTF) operated for 1,184 hours between March 30 and June 30, 2006, at 54 percent uptime and treated 11.620 million gallons of D:\2003_021\ForwardAusdn_spO6.doc 13 Geologic Associates