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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. Forward continues to install 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 2011 monitoring year. With the exception of the current monitoring period, samples were collected quarterly from surface water stations FSW-I and FSW-2. Comparisons of the water quality data from upgradient(FSW-1) and downgradient(FSW-2) surface water stations during the 2011 monitoring year indicates similar concentrations, suggesting that 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 a sump it is pumped into the surface impoundment(WMU F) for evaporation. During the 2011 monitoring year, 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 4.67 to 12.08 feet during the 2011 monitoring year. The results of the annual leachate sample collected during the fourth quarter 2011 indicate that there were no new COCl identified. The results of the LCRS gas test conducted in August 2011 at the Forward Unit indicated that an open-air conduit is present across the LCRS unit, allowing sufficient leachate evaporation. Based on freeboard logs, LCRS gas testing, and observations from Forward personnel, the leachate control facilities were operating effectively during the 2011 monitoring year. 4.5 AUSTIN UNIT 4.5.1 Groundwater Measured groundwater elevations during 2011 generally reflect seasonal precipitation patterns. Hydrographs depicting groundwater elevations over the past 14 years are presented in Appendix D. Overall groundwater flow direction during the 2011 monitoring year were generally consistent with past monitoring periods with flow generally directed to the north and northeast with an average gradient of 0.002 ft/ft. Groundwater quality conditions beneath the Austin Unit during the 2011 monitoring year are generally similar to those observed in the previous monitoring year. For DMP wells, CLs were consistently exceeded in wells AMW-1 3) and AMW-14 and intermittently in C:k201 1-0050\FA_4QI Ldoc 15 Geo-Logic Associates