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Hydrocarbons were detected in only one sample. A TPH-g concentration of 2.98 mg/kg (parts per million) was detected in KF-5 at 11 feet. The results confirm those obtained from the 1998 GeoprobeO borings, which demonstrated that soil contamination is limited to the vicinity of the UST excavation and does not extend to the property boundary wells.. 4.3 Groundwater Samples Significant changes in hydrocarbon concentrations have taken place in the original three wells since they were monitored in January of 1999. Gasoline was not detected in either KF-1 or KF-3, and benzene was close to or below detection limits in both wells. Both TPH-g and benzene were detected in KF-2, but concentrations were considerably lower than in 1999 (Table 3). Toluene and the other aromatics were also near or below detection limits. MTBE was not detected in either KF-2 or KF-3, but a concentration of 47 µg/1 (micrograms per liter=parts per billion [ppb]) was reported in KF-3. We interpret the low concentrations in KF-1 through KF-3 as representative of groundwater concentrations in the upper part of the screened interval in these wells (15-30 feet) rather than the concentration at the soil-water interface(7 feet). Similar results were obtained in KF-4, but because the soil-water interface is within the screened interval, the results are regarded as representative of maximum concentrations in this well. MTBE was detected at a concentration of approximately 6 ppb. Concentrations in KF-5 are also representative of the concentration at the soil-water interface, but are higher. Benzene was detected at 1,410 ppb and MTBE at 63 ppb. No hydrocarbons were detected above standard reporting limits in either of the two newest wells (KF-6 and KF-7). These wells are not within the presently impacted area. 4.4 Extent of Groundwater Contzminat!on Figure 5 is a contour map of TPH-gasoline concentrations for samples collected in July and October. It is clear from the results from KF 4, 6, and 7 that the plume does not extend off site to the east or northeast. The results from the other wells are more difficult to interpret because those samples were collected on a different date and the static water level is above the screened interval in some wells. The results from KF-1, 2, and 3 suggest that the magnitude of the impact is fairly low beneath the site, but the relatively high concentrations in MW-8 and KF-5 give the appearance that conconcentration increase to the south and west of the site. Whether this is the result of activities at the Kwikee Foods site or to an upgradient source to the southwest is uncertain. 5.0 CONCLUSIONS AND RECOMMENDATIONS Integrating the data that were collected from Geoprobe borings GP-1 through GP-5 in 1998 with the data that were collected during the third quarter makes it possible to conclude with good certainty that soil contamination is limited to the southwestern quarter of the site. Concentrations are exceptionally low, and TPH-g is above detection limits in only one of the approximately 25 soil 6