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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 fourth quarter 2007. Leachate samples were collected from the pond 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 and analytical results for the fourth quarter 2007 are presented in Table 3-6. As shown on Table 3-6, 11 dissolved metal constituents were detected with five measured above the PQL; and one SVOCs (bis[2-ethylhexyl] phthalate), a confirmed laboratory contaminant was measured; no VOCs, pesticides, or herbicides were measured in the leachate sample collected during the fourth quarter 2007 monitoring period. Review of the November 2007 leachate sample data indicates no potential new COCs. Therefore, no retesting is required. 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 2,140 hours between October 1 and December 31, 2007, at 96.9 percent up time, and treated 26.797 million gallons of groundwater at an average flow rate of 209 gallons per minute, or 0.301 million gallons per day. During this period, the GTF removed approximately 2.4 pounds of VOCs (CH2M Hill, 2008). 3.2 SUMMARY Groundwater quality conditions beneath the Austin Unit during the fourth quarter 2007 monitoring period are generally similar to historical results. CLs were exceeded in DMP wells AMW-7, AMW-13, and AMW-14, and with the exception of cis-1,2-DCE concentrations measured in well AMW-13, 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 wells AMW-1, AMW-10, and AMW-19, while decreasing VOC trends were noted in CAP wells 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. The annual leachate sample results indicate that there were no new potential COCs. D:12007_0043\Boma rd A u sti n_4Q07.d oc 13 Geologic Associates