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® summarizes CLs that were exceeded in samples collected from groundwater monitoring wells during the third quarter 2006. As summarized in this table, CLs were exceeded for wells MW-1,MW-2A,MW-3, MW-10, MW-13, MW-14, MW-15, MW-16, MW-17, MW-18,MW-19, and MW-21. In accordance with the RPCMP,wells with exceedances of concentration limits(other than arsenic,bicarbonate,hexavalent chromium,nitrate as nitrogen, and sulfate)will be resampled in November during the fourth quarter 2006 sampling event and a second independent sample will be collected in December 2006. The results of the retesting events will be submitted to DTSC and RWQCB under separate cover. 2.1.5 Vadose Zone Monitoring The current vadose-zone monitoring network at the Forward Unit consists of 16 lysimeters. The lysimeter locations are shown on Figure 2-1. Each accessible lysimeter was inspected and vacuums were reset to approximately—80 to—40 centibars on August 28, 2006. On September 26, 2006, the lysimeters were again checked and positive pressure was applied to evacuate the accumulated sample. As recorded in the field notes for lysimeters (Appendix C) and summarized on Table 2-5, only lysimeter LY-BG1 contained soil-pore liquid and was submitted for VOC analysis. The analytical results indicates only one VOC (t-butyl alcohol) was detected in the sample collected from lysimeter LY-BG-1 at a concentration of 35 µg/L. 2.1.6 Surface-Water Monitoring Site run-on and run-off control facilities are designed to effectively channel surface water to lined holding and evaporation ponds on site. According to the Operations Manager, no surface water was discharged from the facility during the reporting quarter. During the third quarter 2006 monitoring period surface water stations FSW-1 and FSW-2 were sampled on August 29, 2006. Table 2-6 summarizes the analytical results for surface water samples collected at the Forward Unit. A comparison of upgradient(FSW-2)to downgradient(FSW-1) surface water samples indicates slightly elevated general chemistry and metals constituent concentrations in the downgradient surface water sample. However,with the exception of dibromochloromethane(a confirmed laboratory contaminant),no VOC were detected at either surface water station during the third quarter 2006 monitoring period. Further monitoring is necessary to evaluate the significance of the elevated general chemistry and metals in downgradient surface water station FSW-1. 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 2006, leachate was observed at holding areas WMW-DO1,WMU-D02, WMU FU-03, WMU FU-04, and WMU FU-05. The other holding areas were reported to be dry by Forward Landfill personnel. Freeboard at WMU F ranged from approximately D:U003 02IWorwerdAn - - 7 Geologic Associates