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The presence of cis-1,2-DCE suggests natural dechlorinization is occurring in the vicinity of wells AMW-1,AMW-10, and AMW-11. As summarized in the Annual Corrective Action Evaluation prepared by Herst&Associates (2006),the overall groundwater quality at the site is generally improving. 3.1.6 Domestic Well Monitoring Two domestic wells(7898-A and 8106-A)were sampled on February 5, 2007. Table 3-3 summarizes the current analytical results for the domestic well samples collected. As shown on Table 3-3, four VOCs were measured in the sample from domestic well 7898-A with all four VOCs measured above the PQL, while five VOCs were measured in the sample from domestic well 8106-A with four VOCs measured above the PQL. 3.1.7 Surface Water Monitoring During the first quarter 2007 monitoring period surface water stations ASW-1 and ASW-2 were not sampled because both surface water stations were reported dry. In addition,time-series plots and trend analyses for the surface water monitoring stations are presented in Appendix D. 3.1.8 Leachate Monitoring According to the Operations Manager,no leachate was taken off site during the first quarter 2007. 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 first 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 first quarter 2007 are presented in Table 3-5. Review of the November 2006 leachate sample data indicates that of the constituents detected, only mercury and pesticides(dicholorvos and naled) are potential new COCs. In accordance with WDR No. R5-2003-0049,verification samples were collected from the Austin leachate sample point on February 7, 2007. The results from the retest indicates that only mercury was confirmed in one of the retest samples at an estimated trace concentration(Table 3-5) and has been added to the COC list for the Forward Landfill. D:UO07_0043\ForwardAustin_w07.doe 12 Geologic Associates