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3.0 CONCLUSIONS, RECOMMENDATIONS AND PROJECT STATUS Between June 9, and August 23, 2004, the groundwater surface dropped an average of 1 29 feet, the groundwater gradient increased from 0 0020 to 0 0022 foot/foot, and the general direction of groundwater flow remained toward the east The groundwater surface configuration appears to be consistent with historical and seasonal trends Between June 9, and August 23, 2004, the concentrations ofasoline compounds pounds m groundwater generally decreased in MW-2 and MW-6, and increased slightly in MW-4 Gasoline hydrocarbons are concentrated as free product near former UST#3, and concentrations of gasoline compounds decrease with distance from the source area As shown on the isoconcentration maps, the lateral extent of MTBE in groundwater is mostly defined (Figure 7), and the lateral extents of TPH-as- gasoline and benzene in groundwater remain undefined to the west of the source area (Figures 5 and 6) The vertical extent of impacted groundwater has not been investigated On October 5, 2004, the thickness of free product in MW-1 increased significantly Consistent with the trends for 2003, the increase may be due to the seasonal lowering of the groundwater table during the summer and fail months Based on these conclusions, Ramage Environmental recommends that the previously-approved remedial feasibility testing tasks be initiated during the first quarter of 2005 The first task should be the installation of the nested soil vapor extraction well and nested air sparge/soil vapor extraction well During this drilling work, another groundwater monitoring well should be installed to the west of MW-6, to further define the lateral extent of impacted groundwater In the meantime, monthly free product removal and quarterly groundwater monitoring should continue 7