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COMPLIANCE 1 , D During the 2006 monitoring year, CL were consistently exceeded in Forward Unit wells MW-lA, MW -2A, MW -3A, MW -10, MW -13, MW -14, MW -15, MW16, MW -17, MW -18, MW -19, and MW -21 and sporadically in well MW -23R. The inorganic CL exceedances have been measured and verified in retest samples collected from the monitoring wells at the Forward Unit, followed by NRD. In each case the NRD has concluded that the CL exceedances are likely the result of naturally occurring conditions and therefore not indicative of a release from the Forward Landfill. 4.4.1 Groundwater Measured groundwater elevations during 2006 were generally static reflecting seasonal precipitation patterns. Hydrographs depicting groundwater elevations over the past six years are presented in Appendix D. The groundwater flow direction during 2006 varied between 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 2006 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 -1 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 2006 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. D: 0003_021 TorwardAusNn_ft.docl 15 Geologic Associates