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8820101-R COT-9 contamination was MW1-45 taken at a depth of 46 feet in Boring MW-1. Only moderate to low levels of benzene and xylene were found in that sample. Groundwater Contamination No free product or sheen were detected in Wells MW-1 and MW-2, while MW-3 did not contain enough water to collect a sample. As shown in Table 1, ' Well MW-1 contained significant levels of contamination at 92 mg/l {ppm} TPH and 15.0, 18.4, 5.0 and 43.8 ppm BTEX, respectively. Well MW-2 was also found to be contaminated with 12.2 ppm TPH and 9.7, 0.4, 0.6 and 1.6 ppm BTEX. No lead was detected in either well sample, while only Well MW-1 was found to contain detectable EDB at 0.012 ppm. The state action levels for BTEX are 0.0007, 0. 1, 0.68 and 0.62 ppm, respectively. As shown in Table 1, all action levels have been exceeded in Well MW-1 and partially texceeded in MW-2. CONCLUSIONS It is apparent from the results of this investigation that varying degrees of hydrocarbon contamination are present in both the soil and groundwater at the site. Based on field observation and analytical testing for both this and the previous assessment conducted by Hydrotech, the apparent source of the contamination is located near the southeast corner of the storage tank cluster. The majority of the soil contamination appears to be above 40 feet in depth, although the contamination in the sample at 46 feet in Boring MW-2 would indicate that low levels of contamination did extend to the groundwater at that location. ' The presence of high levels of groundwater contamination in MW-1 and moderate levels in MW-2 would suggest that significant levels of hydrocarbons extended to groundwater somewhere in the vicinity of the wells. It is assumed that the actual source is or was centered beneath one of the tanks in the east portion of the tank cluster, and the soil 12