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2.1.5 Vadose Zone Monitoring The current vadose-zone monitoring network at the Forward Unit consists of 17 lysimeters. The lysimeter locations are shown on Figure 2-1. Each accessible lysimeter was inspected and vacuums were reset to approximately—25 inches of mercury on July 29, 2010. On August 25, 2010, 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, all lysimeters were reported dry, and as a result, no soil-pore liquid samples were collected during the current monitoring period. 2.1.6 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 2010, leachate was observed at all of the holding areas except WMU D-87 and WMU D-88 A/B. Freeboard at WMU-F ranged from approximately 7.75 to 11.92 feet during the third quarter 2010 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, specific conductance, and temperature. Results of monthly field monitoring measurements for the third quarter 2010 are presented in Table 2-6. Value Engineering conducted a gas test of the leachate collection and removal system (LCRS) on August 27, 2010 at the Forward Unit. The test results indicate that an open- air conduit is present across the LCRS units, and no excessive leachate is backed up in the drainage layer or sump of the LCRS units. A summary of the test results is provided in Appendix A. 2.1.7 Surface Water Monitoring Site run-on and run-off control facilities are designed to effectively channel surface water to site stormwater/sedimentation ponds. According to the Operations Manager, there were no discharges to surface water during the reporting quarter. On August 26, 2010, Del-Tech reported that surface-water locations FSW-1 and FSW-2 were dry. 2.2 SUMMARY Groundwater quality conditions beneath the Forward Unit during the third quarter 2010 monitoring period are generally similar to those observed in previous monitoring periods. During the third quarter 2010 monitoring period, five new historical intrawetl maximum values were measured in samples collected from groundwater monitoring wells. The D:\30 t 0_00 t 3\FA_3Q t o.doc 7