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Lead was not detected in any of the wells, and samples from KF-4, KF-6, and KF-7 continue to be below reporting limits for all hydrocarbons. Except for xylene, concentrations also remained below the reporting limits in KF-1. In KF-2, MTBE, xylene, and TBA concentrations rose slightly, and these as well as gasoline and benzene rose in KF-3 and KF-5. Hence, the concentration of most hydrocarbons increased slightly in at least three wells this quarter. 4.3 Hydrocarbon Plume Maps The contour maps that were included in the First Quarter 2002 Report were based on February data from both the Kwikee and Chevron sites, and illustrated a dissolved-phase gasoline plume that was centered near MW-1 at the Chevron site. The plume extended eastward to the beyond KF-5 at the Kwikee site but only MTBE extended eastward far enough to reach KF-2. A decreasing concentration gradient from west to east was clearly evident, reflecting the fact that concentrations beneath the Chevron site are two orders of magnitude (100 times) greater than those beneath the Kwikee site. This eastward concentration gradient is still evident in the contour maps for May 2002 (Figures 4- 6), although the plume cannot be fully mapped because Upgradient Environmental was unable to obtain the May 2002 laboratory data from Gettler-Ryan for the Chevron site. Several messages requesting the data were not returned. Hence, these maps are based only on the data from the Kwikee monitoring wells. Increases in concentrations in KF-3 and KF-5, as well as the detection of xylene and an increase in the MTBE concentration in KF-2, imply that the plume has shifted eastward slightly since February. This shift occurred while the remediation system at the Chevron site was inoperative and the groundwater flow direction reverted to its natural eastward direction, and is a further confirmation that dissolved hydrocarbons migrate eastward from the Chevron site in the absence of measures at that site to counteract normal groundwater flow. When the remediation system was in operation during the first quarter of 2002, concentrations at the Kwikee site were diluted by uncontaminated water that was drawn in from farther east. 5.0 CONCLUSIONS AND RECOMMENDATIONS The data collected during the second quarter of 2002 reveal that the water table in the immediate vicinity will rebound when no remedial activity is taking place at the Chevron site, and groundwater will return to its natural eastward flow direction. This process does not occur overnight, and water depth measurements in May indicate that the water table has equilibrated below the Kwikee Foods site but not beneath the Chevron site. As a result, groundwater continued to flow westward west of the Kwikee site, but began flowing eastward beneath the site. In response, hydrocarbon concentrations beneath the Kwikee site began increasing'again as the higher concentrations that are present beneath Franklin Street began migrating eastward. The increase in concentrations in KF-3 contradicts the January 2002 suggestion by PHS/EHD that higher soil concentrations may exist east of that well near the former UST cavity, causing concentrations to increase when groundwater flows to the west from the excavation toward KF-3. 5