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3.1.8 Leachate Monitoring According to the Operations Manager,no leachate was taken off site during the second quarter 2009. 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 2009. Leachate samples were collected from the pond on a monthly basis and analyzed in the field for pH and specific conductance. The results of monthly field monitoring measurements 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 four wells (EW-1, EW-2, E -3, and EW-4), treated, and discharged to an infiltration pond. During the monitoring period-Forward completed repairs to groundwater extraction wells EW-1 and EW-2 which included well development and pump rehabilitation. In addition,recently constructed groundwater extraction wells EW- 3 and EW-4 were brought online in May 2009. It should be noted,however, that extraction well EW-3 was taken offline due to an insufficient water column in the well for the pump to operate. During the monitoring period the GTF treated 17,475,700 gallons of groundwater at an average flow rate of 141 gallons per minute, or 203,206 gallons per day. During the monitoring period,the GTF removed approximately 2.65 pounds of VOCs. 3.2 SUMMARY Groundwater quality conditions beneath the Austin Unit during the second quarter 2009 monitoring period were generally similar to historical results. CLs were exceeded in DMP wells AMW-6, AMW-7, AMW-13, and -14,however,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 CAP wells AMW-1, AMW-10,and AMW-19, while decreasing VOC trends were noted in CAP wells AMW-4, -5/5R, AMW-10, and AMW-11. The increasing cis-1,2-DCE trends in wells AMW-1 and AMW-10 suggest that active reductive dechlorination is occurring in the vicinity of these wells. D:\2009 OOITFA_2Q09.doc 13 Geologic Associates