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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. As requested by PHS/EHD, we attempted to construct a groundwater gradient map by integrating the data that were collected by Gettler-Ryan for the Chevron site on the west side of Franklin Street. However, a geologically reasonable and consistent map could not be constructed, due to several errors in the data. These included incorrectly located wells (e. g. both MW-6 and MW-10 are incorrectly located on the Gettler-Ryan map),'changes in casing elevations (e. g. the elevation of MW-2 was previously shown as 1.95 feet, but is now listed as 1.33 feet), and perhaps faulty water- depth measurements. The data from KF-4 and KF-5 are particularly suspect; comparison to the data from December 2000 shows that the static water level rose a few inches in these wells, but more than a foot in the other five wells at the Kwikee site. Therefore, no gradient map is included with this report. 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-1, KF-2, KF-4, KF-6 and KF-7). This confirms our previous conclusion that the majority of the site is not within the impacted area. Benzene had been detected near the reporting limit in KF-4 in December, implying that this well was near the eastern limit of groundwater contamination, and the sample from February 2001 validates that conclusion. Benzene and Total Petroleum Hydrocarbons as gasoline (TPH-g) were detected in both KF-3 and KF-5, but the concentrations in KF-3 were higher than in December and lower in KF-5. Methyl tertiary butyl ether(MTBE) remained about the same in KF-3, but decreased in KF-5.Nevertheless, the results confirm those of the previous two quarters, which showed that contamination beneath the property is limited to the southwestern corner of the site. 5.0 CONCLUSIONS AND RECOMMENDATIONS , Due to the lack of consistent and reliable location maps and casing surveys, it is currently not possible to develop a valid picture of the groundwater gradient and flow direction in the vicinity of the site. We have discussed this problem with Secor international and Gettler-Ryan, and the consensus is that the most cost-effective solution to this problem would be to retain a professional surveyor to jointly survey all three sites (Kwikee Foods, Chevron, and Boulevard Automotive) during the second quarter of 2001_ Secor will obtain a cost estimate for this service. Laboratory results have begun to show a consistent trend for the Kwikee Foods site, suggesting that contaminants are limited to the southwestern portion of the property. We recommend that 3