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pumped into the surface impoundment( U F) for evaporation. During the fourth 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 11.92 feet to 12.00 feet during the fourth 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 field measured for pH and specific conductance. Of note, no leachate sample was collected on October 12, 2009 because the surface impoundment was reported dry. 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 measurements, and analytical results for the fourth quarter 2009 are presented in Table 2-6. As shown on Table 2-6, 11 dissolved metal constituents were measured with six above their PQL; nine VOCs were measured with five above their PQL; and four semi-volatile organic compounds(SVOCs) were measured above their PQL in the leachate sample collected during the fourth quarter 2009 monitoring period. No herbicides or pesticides were detected in the leachate sample. The results of the annual leachate sample indicate that there were no new COCs detected, and as a result, verification testing is not required. 2.2 SUMMARY Groundwater quality conditions beneath the Forward Unit during the fourth quarter 2009 monitoring period are generally similar to those observed in previous monitoring periods. During the fourth quarter 2009 monitoring period, two new historical intrawell maximum values were measured in samples collected from groundwater monitoring wells,which nominally exceeded their previous intrawell maximum values. During the monitoring period,two VOCs were measured above their PQLs and one trace-level VOC was measured in the sample collected from well M -10. One CL was exceeded for TCFM in the sample collected from well MW-10 during the current monitoring period. The sporadic detection of low-level VOCs in groundwater(and lysimeter samples) at the Forward Unit are most likely due to landfill gas from unlined unit WMU-B and have been previously documented in a letter report dated February 14,2001 (RWQCB Case No. 2209). The fourth quarter 2009 leachate monitoring results are generally similar to those observed historically. During the monitoring period, 11 dissolved metal constituents were measured with six above their PQL; nine VOCs were measured with five above their PQL; and four SVOCs were measured above their PQL in the leachate sample collected during the fourth quarter 2009 monitoring period. No herbicides or pesticides were detected in the leachate sample. The results of the annual leachate sample indicate that there were no new COCs identified, and therefore, verification testing is not required. During the fourth 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. D:\2009_0017\FA_4Q09.doc G@OLOgIC ASSOCIat@S