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3.0 PROCEDURES Groundwater monitoring took place on December 11, and a groundwater gradient map was prepared(Figure 3). Except for the 1-inch diameter wells (KF-6 and KF-7), a two-stage submersible pump was used to purge the wells. Water temperature and conductivity were measured during purging. The purged water is stored in 55-gallon drums on the east side of the property. Depth measurements and purging data are shown in Appendix A. After purging, water samples were collected with a disposable plastic bailer and poured into 40-m1 vials. The vials were labeled, logged, placed in a cooled ice chest, and transported to Sequoia Analytical for analysis. The laboratory report and chain of custody form are in Appendix B. 4.0 RESULTS 4.1 Depth to Groundwater and Groundwater Gradient The depth to groundwater and the calculated elevation of the static water level since 1995 are shown in Table 1. The static water level declined slightly (approximately 0.1 foot) during the fourth quarter. At the same time, the groundwater flow direction rotated counterclockwise and now slopes relatively uniformly to the northwest at a gradient of 0.0028 ft1ft (Figure 3). This is more normal than the exceptionally flat but non-planar gradient that was observed in September. However, it is the first time that a northwestward flow direction has been observed. 4.2 Groundwater 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 four of the six wells (KF-1, KF-2, KF-6 and KF-7). This confirms our previous conclusion that KF-6 and KF-7 are not within the impacted area, and extends this conclusion to include the two wells that are located closer to the former tank cavity. In addition, only benzene was detected in KF-4, at the very low concentration of 1.7 µg/l (parts per billion), which implies that this well is located at the extreme eastern limit of groundwater contamination. Hence, much of the site is free of groundwater contamination. Methyl tertiary butyl ether ,(MTBE) was detected in both KF-3 and KF-5, and Total Petroleum Hydrocarbons as gasoline (TPH-g) concentrations in these wells were reported at 679 µg/l and 3,290 µg/l, respectively. Some or all of the BTEX compounds were also detected in both wells. Because these wells are located west and south of the former tank cavity, they imply that groundwater contamination is probably centered off the site beneath Franklin Street or Country Club Boulevard. This further implies that the source of contamination is located south or west of Kwikee Foods, because the prevailing groundwater flow direction has been to the east or northeast 3