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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 first quarter 2008, 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, and WMU FU-06. The other holding areas were reported to be dry by Forward Landfill personnel. Freeboard at WMU-F ranged from approximately 6.17 feet to 9.58 feet during the first quarter 2008 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 for the first quarter 2008 are presented in Table 2-7. 2.2 SUMMARY Groundwater quality conditions beneath the Forward Unit during the first quarter 2008 monitoring period are generally similar to those observed in previous monitoring periods. During the first quarter 2008 monitoring period,no new historical intrawell maximum values were measured in samples collected from groundwater monitoring wells. Estimated trace-level VOCs were measured in wells MW-10 and MW-14; and one VOC was measured above the PQL in well MW-14. CLs were exceeded for one or more monitoring parameters in samples from 11 wells. In accordance with the RPCMP, six wells with exceedances of CLs that are potential impact constituents will be resampled in May 2008 (during the second quarter 2008 sampling event), and a second independent sample will be collected in June 2008. The results of the two retests will be submitted to DTSC and RWQCB under separate cover. Historically, similar exceedances of inorganic CLs have been measured and verified in samples collected from DMP monitoring wells at the Forward Unit, followed by no release demonstrations (NRDs),which have concluded that the inorganic CL exceedances are likely the result of naturally occurring conditions and therefore not indicative of a release from the Forward Landfill. During the January inspection,methane exceeded the regulatory limit of five percent in perimeter soil-pore gas probe GP-9A at the Forward Unit. Minor adjustments were made to the LFG extraction system, and as a result, methane concentrations in this probe were reduced to 0.1 and 0.2 percent during the February and March inspections. 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:\2007_0043\FA_1Q08.doc 7 Geologic Associates