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fine-grained interval is a downward-coarsening sand bed The sand is silty to fine grained in the upper part, but becomes coarse grained and gray near the base, which occurs at a depth of 32 5 feet in SW-1 and at 31 feet in VT-1 Below the sand bed is a layer of blue-gray silty clay 4.2 Soil Contamination Although VT-1 was drilled within the area that had been previously mapped as part of the soil contaminant plume, no hydrocarbon vapors or other indications of contamination were observed during drilling, and no hydrocarbons were detected by the laboratory in any of the soil samples (Table 2) Based on these results, the eastern edge of the soil plume must be moved westward, and the overall size of the plume is smaller than previously estimated Sparging well SW-1 was drilled in the approximate center of the mapped soil plume, and hydrocarbons were detected in three of the four soil samples that were collected, but at concentrations that were lower than expected Xylene was detected at the reporting limit at a depth of 20 feet, and all BTEX compounds plus TPH-g were detected at both 25 and 30 feet Concentrations increase downward to the base of the sand bed, where the coarsest, most permeable sand is present None of the gasoline oxygenates were detected in any of the samples 4.3 Depth to Groundwater The depth to groundwater has increased by about 6 inches since May (Table 1) The static water level now averages about 32 feet (16 feet below mean sea level) and is still at least 12 feet above the screened interval in the first three wells and 2 5 feet over the screen in VM-4 4.4 Groundwater Gradient Figure 3 illustrates the groundwater gradient and general direction of groundwater flow The gradient is essentially unchanged since October 1998, and is more consistent than we have observed at most sites Flow is to the east 4.5 Groundwater Contamination Concentrations of TPH-g and BTEX in VM-1 and VM-2 have increased since the first quarter of this year, and benzene and other aromatic compounds have now appeared in VM-3 as well This is in contrast to VM-4, in which BTEX compounds have been on a decreasing trend since this well was first sampled(Table 3) None of the oxygenates were detected in any of the wells (Table 4) 5.0 SENSITIVE RECEPTOR SURVEY A sensitive receptor survey was conducted in the third quarter Upgradient personnel reviewed • the well log files of the California Department of Water Resources in Sacramento, and conducted 5