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5.83 feet to 7.33 feet during the third quarter 2006 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. The results of monthly field monitoring measurements for the third quarter 2006 are presented in Table 2-7. Value Engineering conducted a gas test of the leachate collection and removal system (LCRS) on August 10, 2006 at the Forward Unit. The test results indicate that an open- air conduit is present across the LCRS unit, and no excessive leachate is backed up in the drainage layer or sump of the LCRS unit. 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 2006 monitoring period are generally similar to those observed in previous monitoring periods. Fifteen new historical intrawell maximum values were measured,including seven first- time VOC detections, in samples collected from groundwater monitoring wells. However, all seven first-time VOC detections are confirmed laboratory contaminants. Excluding confirmed laboratory contaminants, one or more trace-level VOCs were measured in wells MW-10, MW-14, and MW-21. In addition,PCE was measured above the PQL in the sample collected from well MW-14. The Forward Unit remains in corrective action proof monitoring for corrective actions implemented in 1995 for intermittent low-level VOCs. CLs were exceeded for one or more monitoring parameters in samples from 12 wells. In accordance with the RPCMP, the seven wells with exceedances of CLs for impact constituents will be resampled in November 2006 during the third quarter 2006 sampling event and a second sample will be collected in December 2006. The retest results will be submitted to the DTSC and RWQCB under separate cover. Historically, similar exceedances of inorganic constituent CLs have been measured and verified in samples collected from DMP monitoring wells at the Forward Unit, followed by no release demonstrations (NRD), 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. Forward is currently installing additional landfill gas extraction wells, and working to optimize the efficiency of the landfill gas extraction system. During the third quarter 2006 monitoring period, methane was measured at concentrations less than five percent in perimeter soil-pore gas probes, suggesting that the landfill gas extraction system is effectively reducing methane concentrations along the perimeter of the Forward Landfill. • D*\2003 021\Fomar"usdn=m06.doc 8 Geologic Associates