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2.1.7 Leachate Monitoring Leachate sumps are inspected for the presence of leachate and observations are recorded at least weekly by Forward Landfill personnel. If leachate is detected in a sump, it is pumped into the surface impoundment (WMU F) for evaporation. During the third quarter 2009, leachate was observed at holding areas WMU D-89, WMU D-93/94, WMU D-01,WMU D-02, WMU FU-03, WMU FU-04, WMW FU-05,WMU FU-06, and WMU FU-08. The other holding areas were reported to be dry by Forward Landfill personnel. Freeboard at WMU-F ranged from approximately 10.08 feet to 12.00 feet during the third quarter 2009 monitoring period. Appendix A presents copies of the leachate logs and the freeboard observation logs. Leachate samples were collected on a monthly basis and analyzed in the field for pH and specific conductance. Results of monthly field monitoring measurements are presented in Table 2-7. Of note, no leachate sample was collected on September 10, 2009 because the surface impoundment was reported dry. Value Engineering conducted a gas test of the leachate collection and removal system (LCRS)on August 21, 2009 at the Forward Unit. The test results indicate that an open- air conduit is present across the LCRS units, and no excessive leachate is backed up in the drainage layer or sump of the LCRS units. A summary of the test results is provided in Appendix A. 2.2 SUMMARY Groundwater quality conditions beneath the Forward Unit during the third quarter 2009 monitoring period are generally similar to those observed in previous monitoring periods. During the third quarter 2009 monitoring period, one new historical intrawell maximum value was measured for arsenic in the sample collected from groundwater monitoring well MW-16, which nominally exceeded the previous maximum value. Excluding suspected field/laboratory contaminants, five estimated trace-level VOCs were measured in well MW-10. One CL was exceeded for arsenic in the sample collected from well MW-19 during the current monitoring period. However, in accordance with the RPCMP guidelines, arsenic,bicarbonate, hexavalent chromium, nitrate as nitrogen, and sulfate, are not considered impact constituents, and therefore, arsenic will not be retested. During the third quarter 2009 monitoring period, methane concentrations did not exceed the regulatory limit of five percent in perimeter soil-pore gas probes at the Forward Unit. Forward continues to install additional landfill gas extraction wells (as needed), and makes regular adjustments to the landfill gas extraction system to optimize efficiency of the landfill gas extraction system. D:\2009_0017\FA_3Q09.doc 7 Geologic Associates