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® 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 second quarter 2006 monitoring period surface water stations FSW-1 and FSW-2 were sampled on May 23,2006. 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 generally similar concentrations. Overall the sample results indicate that the landfill operations are not impacting surface water quality. 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 second 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 5.25 feet to 7.83 feet during the second quarter 2006 monitoring period. Appendix A presents copies of the leachate logs and the freeboard observation logs. e collected on a monthly basis and analyzed in the field for pH and Leachate samples were y Yz specific conductance. The results of monthly field monitoring measurements for the second quarter 2006 are presented in Table 2-7. 2.2 SUMMARY Groundwater quality conditions beneath the Forward Unit during the second quarter 2006 monitoring period are generally similar to those observed in previous monitoring periods. Sixteen new historical intrawell maximum values were measured,including seven first- time VOC detections, in samples collected from groundwater monitoring wells. In addition, one or more trace-level VOCs were measured in wells MW-1B, MW-10, MW-14, MW-15,MW-16,MW-17,MW-19, MW-21, and DW-9690,while concentrations of PCE and TCE in well MW-113 and acetone in well DW-9690 were measured above the PQL. 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, wells with exceedances of CLs for impact constituents will be resampled in August 2006 during the third quarter 2006 sampling event and a second sample will be collected in September 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 D:\2003-021\ForwardAustin—sPO6.doc 8 Geologic Associates