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would begin to rise and probably peals between June and September This prediction held true, as the TPH-g concentration rose by 48% and the total BTEX concentration rose by 16% We also reported in the Second Quarter 2002 Report that concentrations in VM-1 are on a downward trend, and this remained true during the third quarter The TPH-g concentration declined 21%, and the total BTEX concentration fell by 50% (Table 2 and Figure 5) In contrast to VM-I and VM-2, concentrations in VM-3 and VM-4 are rather stable Except for four quarters between. late 2000 and late 2001, TPH-g concentrations in VM-3 have hovered between 112 and 180 ppb Benzene and ethylbenzene concentrations have been consistently low, and have been below the detection limit for more than a year Toluene and xylene concentrations have generally declined during the last few years, and have remained near 1 ppb for several quarters Concentrations of all analytes have been slightly higher and more variable in VM-4 Because many samples have been analyzed in the past for gasoline oxygenates and the data clearly indicate that oxygenates are not a significant component of the contaminant plume, no samples were analyzed for these compounds 5.0 CONCLUSIONS Groundwater continued to flow to the east-northeast during the quarter This has been the predominant flow direction throughout the investigation of the site Contaminant concentrations have been rather stable since the first quarter of 2002 Historical trends now clearly indicate that contaminant concentrations increase during the third quarter and reach their annual peak This peak shows no relationship to the static water level, which has varied from 31 to 35 feet during the third quarter, and is within the same range as in other quarters Overall, concentrations are increasing in VM-2 and decreasing in VM-1, indicating that the core of the contaminant plume is migrating east-northeast in the predominant direction of groundwater flow Y • 4