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from surface water monitoring stations ASW-1 (upstream) and ASW-2 (downstream) on August 2, 2013 for the third quarter 2013 monitoring period. Table 3-5 summarizes the current analytical results of surface water samples collected at the Austin Unit. As shown on Table 3-5,toluene was measured at a trace concentration at surface water monitoring station ASW-2. Analytical results for the surface water samples are generally similar, suggesting that landfill operations are not impacting surface water quality. Leachate Monitoring According to the Operations Manager,no leachate was taken off site during the third quarter 2013. 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 third quarter 2013. Leachate samples were collected 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. Groundwater Treatment Facility Operations The Groundwater Treatment Facility(GTF) at the Austin Unit has been operational since 1994 to mitigate impacts from landfill releases. Impacted groundwater is extracted from five wells (EW-1, EW-2, E -3, EW-3 , and E -4)that pump groundwater through an air stripper treatment system to remove VOCs. Treated groundwater is discharged to an infiltration pond (constructed in 2003)north of the Austin Road Unit of the Forward Landfill. Due to limited recharge in extraction well EW-3,the well was taken offline and replaced with extraction well EW-3R. To increase the volume of groundwater recovered in this area, well EW-3R was installed adjacent to and deeper than well EW-3. During the monitoring period,the GTF treated 20,430,500 gallons of groundwater at an average flow rate of 215,058 gallons per day. During the monitoring period, it is calculated that the GTF removed approximately 2.22 pounds of VOCs. 3.2 SUMMARY Groundwater quality conditions beneath the Austin Unit during the third quarter 2013 monitoring period were generally similar to historical results. During the current monitoring period, non-statistical exceedances for VOCs were identified at DMP wells AMW-6 and AMW-13. Trend analyses indicate that statistically significant increasing temporal trends were calculated for PCE and TCE in well AMW-13. These results are similar to previous results and it has been recommended that wells AMW-6,AMW-13, and AMW-14 be re-designated as CAP wells since they have historically contained VOCs. For the routine inorganic monitoring parameters, CLs were exceeded for constituent concentrations in DMP wells AMW-7,AMW-12, and AMW-13. Trend analyses indicate that statistically significant increasing temporal trends were calculated CA201"0217A_3QB.doc 12 Geo-Logic Associates