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• 5.0 RECOMMENDATIONS The historical record of water samples from KF-3 and the nearest Chevron well (MW-6) is shown in Figure 8. Thirteen samples have been collected from KF-3 since April 1990, and thirty-five samples have been collected from MW-6 since October 1992. The data from MW-6 are included because they can be used as a proxy for KF-3 for quarters during which no samples were collected from it. Using the fluctuations in concentrations in MW-6 as a guide, quarter-to-quarter variations in concentrations in KF-3 are shown schematically by the dashed line. The Chevron well clearly shows a decline from more than 40,000 ppb to less than 5,000 ppb over the 8-year monitoring period, and even without the dashed line a decreasing trend (from 20,000 ppb to less than 1,000 ppb) is also evident in KF-3. In view of this trend, and with the knowledge that active groundwater remediation in the core of the contaminant plume is presently underway at the Chevron site, we conclude that active remediation of the groundwater beneath the Kwikee Foods site is neither necessary nor cost-effective, nor should it be the responsibility of Mr. Peters. Nearly all of the decrease in concentration shown in Figure 8 took place before active remediation at the Chevron site began, and now that remediation is taking place, further decrease is likely. It appears that the remediation system at the Chevron, site has already affected the groundwater flow direction at the Kwikee site, because gradient lines have recently indicated that groundwater has begun to flow northward or northwestward, rather than eastward. Exactly how this has taken place is not known, but flow to the northwest will accelerate the decline in contaminant concentrations as hydrocarbons are drawn westward toward the Chevron remediation wells. Installing a remediation system at Kwikee Foods could thwart this process by disrupting the flow pattern and causing contaminants to be drawn from the Chevron wells. Therefore, we recommend that no steps be taken to actively remediate the Kwikee site. In order to confirm that further remediation of the Kwikee site will take place without installing any type of remediation system, we recommend continued groundwater monitoring on a quarterly basis through the end of 2001. If concentrations continue to decline and show no tendency to reverse, a Site Closure.Report should be prepared during the first quarter of 2002. I f ' 7