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2.2 SUMMARY Groundwater quality conditions beneath the Forward Unit during the fourth quarter 2007 monitoring period are generally similar to those observed in previous monitoring periods. Ten new historical intrawell maximum values were measured in samples collected from groundwater monitoring wells during the fourth quarter 2007 monitoring period. 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 13 wells. In accordance with the RPCMP, seven wells with exceedances of CLs that are potential impact constituents will be resampled in February 2008 (during the first quarter 2008 sampling event), and a second independent sample will be collected in March 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 (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. During the fourth quarter 2007 monitoring period no methane exceeded the regulatory limit of 5 percent in perimeter soil-pore gas probes at the Forward Unit, suggesting an overall improvement in landfill gas at the site. 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. The results of the annual leachate sample indicate that of the constituents detected; only benzoic acid is a potential new constituents of concern(CDCs). A verification sample will be collected from the Forward leachate sample point in May 2007 and the results will be reported with the second quarter 2008 monitoring report. 3.0 AUSTIN UNIT 3.1 WATER QUALITY MONITORING 3.1.1 Sampling and Laboratory Analyses During the fourth quarter 2007, depth-to-water measurements were recorded in the groundwater monitoring wells on November 5, 2007 and the Austin Unit's DMP and CAP groundwater monitoring wells and surface water monitoring stations were sampled by ATC between November 5, and 7, 2007. A single sample set was collected from each sample point with sufficient liquid and submitted to BC for analysis of the parameters stipulated in RWQCB Order No. R5- 2003-0049. Table 2-1 presents the monitoring schedule and summarizes the analytical methods utilized during the current monitoring period. Water quality samples were also analyzed in the field for dissolved oxygen, turbidity, temperature, specific conductance, D:12007_0043To ncard A u stin_4Q07.doc 8 Geologic Associates