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from the Forward Landfill. On behalf of Forward, GLA has submitted a request to the DTSC to update the CLs for the Forward Unit. In response to continued detection of VOCs in groundwater downgradient of the Austin Road Unit, the RWQCB issued a CAO on December 8, 2009. Forward has recently installed four additional groundwater monitoring wells downgradient of the Austin Road Unit and is currently in the process of evaluating the vertical and lateral extent of groundwater impacts downgradient of the facility. 4.4 FORWARD UNIT 4.4.1 Groundwater Measured groundwater elevations during 2008 were generally static reflecting seasonal precipitation patterns. Hydrographs depicting groundwater elevations over the past 11 years are presented in Appendix D. During the 2008 monitoring year, the groundwater flow direction was generally to the north and northeast toward the Austin Unit with an average hydraulic gradient of 0.001 ft/ft. Groundwater quality conditions beneath the Forward Unit during the 2008 monitoring year are generally similar to those observed in the previous monitoring year. Low-level VOCs were consistently detected in DMP wells M -10 and MW-14. 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 2008 monitoring year. With the exception of the fourth quarter monitoring period, 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 D:\2008_0010\FA_4Q08.doc 15 Geologic Associates