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4.0 RESULTS 4.1 Depth to Groundwater and Groundwater Gradient The depth to groundwater and the calculated elevation of the static water level are shown in Table 1. The static water level has risen since the previous monitoring event in February, and now averages 7.8 feet below grade. Using the water depth measurements and the elevations of the well casings as previously surveyed in the third quarter of 2000, we contoured the hydraulic gradient and determined the direction of groundwater flow (Figure 3). The gradient is slightly mounded in the central portion of the site, where the elevation of the piezometric surface is between 5.78 and 5.80 feet below sea level. To the north and south, the elevation is slightly lower. Hence, it appears that groundwater could be flowing northward in the northern part of the site but southward in the southern part of the site. However, it is important to keep in mind that the elevation differences are very small (a few hundredths of a foot). Thus, it is likely that the water table is essentially flat, and that gravitational influences are exerting little or no influence on groundwater flow. 4.2 Laboratory Results The laboratory results are summarized in Table 2, and the full laboratory report is included in Appendix B. No hydrocarbons were detected above standard reporting limits in five of the seven wells (KF-i, KF-2, KF-4, KF-6 and KF-7). This further confirms our previous conclusion that the majority of the site is not within the impacted area. The MTBE and Total Petroleum Hydrocarbons as gasoline (TPH-g) concentrations in KF-5 have risen slightly since February 2001, but the benzene concentration is unchanged. In contrast, the benzene and TPH-g concentrations in KF-3,declined significantly, while the MTBE concentration remained about the same. A slight decrease in the xylene concentration was also detected. 5.0 CONCLUSIONS AND RECOMMENDATIONS Laboratory results have been consistent for the past four quarters: contaminants are limited to the two southwestern wells and are gradually decreasing in concentration. This trend began to emerge after the groundwater remediation system became operational at the former Chevron site on the west side of Franklin Street. Further, the hydraulic gradient has been less consistent since this system became operational, and the groundwater flow direction is no longer uniformly eastward. These observations suggest that the Chevron remediation system is affecting both the contaminant plume and the hydraulic gradient in a positive way, and that groundwater quality beneath the Kwikee Foods site is improving. 3