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. 4.0 RESULTS 4.1 Depth to Groundwater The static water level is still more than 10 feet above the screened interval in VM-1, VM-2, and VM-3, and approximately two feet over the screen in VM-4 The depth to groundwater on March 31 averaged slightly more than 315 feet (Table 1) The depth measured in VT-1 is clearly an anomaly, and is regarded as erroneous It is probable that a small amount of residual water was trapped below the screened interval in the well cap As shown by the groundwater gradient map discussed in section 4 2, the static water depth was probably 31 81 feet in VT-1 4.2 Groundwater Gradient Figure 3 illustrates the groundwater gradient and general direction of groundwater flow The water table slopes very slightly to the east at a gradient of 0 0010 ft/ft, and is essentially unchanged since October 1999 The extremely low gradient implies that the groundwater flow rate is negligible The map implies that VT-1 is almost on the same contour line as VM-2, and should therefore have encountered the static water level at 31 81 feet(casing elevation [15 92 ft] + water elevation [15 89 ft] = water depth [31 81 ft]) However, because the well is only 30 feet deep, it could not have encountered true groundwater 4.3 Analytical Results Total Petroleum Hydrocarbons decreased in VM-1, whereas benzene and other volatile aromatic compounds all increased slightly since October 1999 (Table 2) BTEX concentrations also increased in VM-4, although TPH remained below the detection limit TPH concentrations increased in VM-2 and VM-3, while BTEX concentrations decreased Hydrocarbons have now been detected in VM-3 during both of the most recent sampling events, which suggests that the groundwater plume has expanded somewhat to the southeast Considerably higher hydrocarbon concentrations were detected in SW-1 Because the screened interval in SW-I spans the static water level, the results from that well are likely to be more representative of trice hydrocarbon concentrations than are those from the monitor wells These wells are screened deeper in the aquifer, where the water is less contaminated No hydrocarbons were detected in the sample from VT-1, but since the water depth data indicate that the static water level is below the casing, the laboratory results from this well are irrelevant 5.0 CONCLUSIONS AND RECOMMENDATIONS In general, hydrocarbon concentrations have been on the rise for some time, and samples from VM-3 indicate that the plume is gradually migrating eastward However, it is apparent that the 4