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3.1.7 Surface-Water Monitoring Surface-water sampling locations was conducted on August 29, 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 pH values, no CLs were exceeded during the third 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 third 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 third 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 third 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 2,109 hours between June 30 and October 1, 2006, at 94 percent uptime and treated 28.7 million gallons of groundwater at an average flow rate of 227 gallons per minute, or 0.327 million gallons per day. During this period, the GTF removed approximately 1.8 pounds of volatile organic compounds. (CH2M Hill 2006). 3.2 SUMMARY Groundwater quality conditions beneath the Austin Unit during the third quarter 2006 monitoring period are generally similar to historical results. Excluding confirmed laboratory contaminants, CLs were exceeded in DMP wells AMW-7, AMW-13, and AMW-14. In addition, statistically significant increasing VOC concentrations were calculated in well AMW-13,while statistically significant decreasing VOC trends were D-A2083L021\FonmirdAusdn_=ntKdft 13 Geologic Associates