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and total lead Samples from this site have not beim analyzed for diesel since the fourth quarter of . 1998, and the last time diesel was detected was the fourth quarter of 1995 The last time the samples were analyzed for oxygenates was the second quarter of 2002 Oxygenates have previously been detected in VM-4, but not in any samples from VM-2 or VM-3 and only once in VM-1 No samples have previously been tested for `l,2-DCA, EDB, or lead 4.0 RESULTS 4.1 Depth to Groundwater and Hydraulic Gradient The depth to groundwater on November 4 was between 36 and 37 feet, which is one foot deeper than the depth in June 2005 (Table 1) The calculated elevation of the water table is approximately 20 5 feet below sea level in VM-7, deepening to 20 94 feet in VM-6 Figure 3 illustrates the shape of the water table and general direction of groundwater flow In comparison to previous quarters, the contours are more arcuate, indicating that the piezometric surface slopes eastward beneath the site but southward beneath Main Street between VM-8 and VM-6 Beneath the site the hydraulic gradient is 0 0036 ft/ft Beneath Main Street it is slightly steeper, at 0 0046 ft/ft 4.2 Analytical Results As requested by EHD, the samples were analyzed for diesel fuel TPH-d was reported in VM-1, VM-2, VM-4, and VM-7, but in each case the laboratory noted that the chromatogram did not match the diesel standard This same result was observed several years ago, when diesel fuel was part of the regular analytical protocol for this site Because the laboratory concluded at that time that the diesel-range hydrocarbons,were not representative of diesel fuel, TPH-d was deleted from the protocol Based on discussions with the laboratory personnel;we concluded that the results were probably indicative of either,the high molecular weight hydrocarbons in gasoline (i e degraded gasoline) or non-gasoline (halogenated) hydrocarbons, such as those that were detected in VM-1, VM-2, and VM-3 in 1995X1-997 Those compounds were also deleted from the analytical protocol, because they likely originated from a different source and are not within the regulatoryjurisdiction of EHD (see below) Turning to gasoline, concentrations in November were somewhat lower than those measured in June in most wells, but were higher in VM-4 and VM-7 (Table 2) Between January and June, the TPH-g concentration declined by 46% in VM-1, and between June and November it had declined another 25% This represents a total decline of 59% for the year In VM-3, the concentration declined 14% between January and June and 25% between June and November, for a total of 35%for the year In both wells, however, the laboratory noted that the TPH-g concentration was due to a single peak (compound) within the gasoline range The results for the oxygenates and BTEX compounds for both wells indicate that none of those compounds are present at elevated concentrations, which makes it quite apparent that the elevated TPH-g concentrations in both wells must be due to a non-gasoline compound The most likely candidates are trichloroethane or perchloroethane (TCE or PCE), which are chlorinated hydrocarbons that were detected on four occasions between 1995 and 1997, when samples were 3