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4.4 FORWARD UNIT 4.4.1 Groundwater Measured groundwater elevations during 2007 were generally static reflecting seasonal precipitation patterns. Hydrographs depicting groundwater elevations over the past seven years are presented in Appendix D. With the exception of the third quarter 2007, the groundwater flow direction during 2007 varied between the north and northeast toward the Austin Unit with an average hydraulic gradient of 0.001 ft/ft. During the third quarter 2007, lower groundwater levels associated with observed pumping from adjacent agricultural wells resulted in a radial flow pattern from the center of the Forward Unit. Groundwater quality conditions beneath the Forward Unit during the 2007 monitoring year are generally similar to those observed in the previous monitoring year. Low-level VOCs were consistently detected in DMP wells MW-10 and MW-14, and intermittently detected in wells MW-16 and MW-21. On behalf of Forward Inc., GLA prepared a letter report dated February 14, 2001 (RWQCB Case No. 2209), to assess the source and potential impacts of low-level VOCs in groundwater adjacent to the Forward Landfill. The letter report concluded that 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. Forward has continued to minimize gas related impacts to groundwater by minimizing interim fill areas that promote ponding of water. Furthermore, in accordance with CCR Title 27, Section 20937, Forward is currently installing additional landfill gas extraction wells, as needed. 4.4.2 Surface Water 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 2007 monitoring year. With the exception of the first and fourth quarter monitoring periods, where both surface-water stations were reported dry, surface-water stations FSW-1 and FSW-2 were sampled quarterly. Comparisons of the water quality data from upgradient (FSW-1) and downgradient(FSW-2) surface water stations indicates generally similar concentrations and that the landfill operations are not impacting surface water quality. 4.4.3 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 the sump it is pumped into the surface impoundment(WMU F) for evaporation. During the 2007 monitoring year, leachate was only observed at holding areas WMU-D93/94, WMW-DO1, WMU-D02, WMW-FU03, WMW-FU04, WMU-FU05, and WMW-FU06. The other holding areas were reported to be dry by Forward Landfill personnel. Freeboard at WMU F ranged from approximately 5.17 feet to 9.92 feet during the 2007 monitoring year. D:\2007_00431F0nvard Austin_4Q07.doc 15 Geologic Associates