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gradient from MW-4 and MW-5 on the west and south margins of the Chevron site, and this slope to the northeast is a persistent feature that is evident on many of the 20 maps that have been constructed. In Figure 12, this northeast gradient may be as steep as 0.016 ft1ft, which is relatively steep. However, wells to the northeast imply that this northeastward slope did not continue indefinitely, and it is evident that in the eastern portion of the Chevron site the water table sloped in a more eastward direction, with a gradient of about 0.002 ft/ft. Even this gradient did not persist farther to the east, as indicated by the elevation of the water table in KF-2, which was slightly higher than that in KF-3. Using only the data from the Kwikee site, one might have concluded that groundwater flow was westward or southwestward toward KF-3, but the data from the Chevron site preclude this possibility. Rather, the elevation contours bend to the southeast, implying that groundwater flow was generally eastward across the Chevron site, but then turned southeastward on the Kwikee site. 3.2 Years 2 and 3: 1996-1997 The Kwikee Foods site was not monitored in 1996 or 1997, but the data from the Chevron site are extremely enlightening for these years (Figures 13 and 14). During this period, groundwater flow was northward at the Chevron site, and the data from the newly drilled wells farther north (MW-10 through 12) confirm that direction. The depth measurement for MW-1 on August 26, 1997 seems rather spurious, being 0.1 feet higher than in MW-3, which appears to be the more upgradient well. Hence, perhaps the high depth reading in MW-1 indicates the presence of floating product, which would raise the depth measurement slightly. A TPH-g concentration of 95,000 ppb was detected on • that day (Appendix B), and although this is not the highest concentration detected in MW-1, it could be indicative of even higher static concentrations, depending on how the well was purged and sampled. 3.3 Year 4: 1998 By May of 1998, groundwater flow had reversed and a strong southward gradient is evident on both the Kwikee and Chevron sites (Figure 15). In addition, a strong westward gradient had developed in the northwestern portion of the. Kwikee site, causing groundwater flow from KF-1 toward MW-7, MW-1, and MW-2. The latter well appears to have been in a slight groundwater depression, because it was also downgradient of MW-4 on the west side of the site. Most interesting of all, MW-5 was by far the most downgradient well; previously, it had been the most upgradient well. 3.4 Year 5: 1999 The southward gradient did not persist for more than about 6 months. By January of 1999, the northeastward gradient from MW-5 had been reestablished, and it was again the most upgradient of any of the 15 wells (Figure 16). The water table sloped northeastward across the Chevron site at a gradient of 0.0037 ft/ft. Farther north, the water table sloped southward or southeastward. A relatively steep eastward gradient developed along the western side of the Kwikee site, with a narrow, linear trough extending north-northwestward across that site. Depth measurements in MW- 13 -