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• 8 Although a map showing lines of equal concentration of 1, 1-Dichloroethane is not included in this report, the highest level was measured in MW-1, which correlates well with the maps constructed for benzene & TPH-G. CONCLUSIONS : Based upon the results obtained to date, the following conclusions appear to be valid. 1 Except for the minor amounts of benzene & TPH-G encountered at shallow depths in MW-3 , soil contamination is not present above 211611 in the three wells . 2 . Groundwater contamination is present in all three wells, with the highest levels of benzene, toluene, ethylbenzene & TPH-G measured in MW-1 . Total xylenes were highest in MW-3 , the reason for this anomaly is not readily apparent . 3 Based upon the July 13, 1995 sampling event, the hydraulic gradient is to the northeast, which corresponds with other data in the area. MW-1, which is upgradient and the farthest from the . removed UST, should have the lowest levels of groundwater contamination However, as can be seen from TABLE III, that is not the case Except for xylene, MW-1 has the highest levels of benzene, toluene, ethylbenzene, TPH-G, and 1, 1-Dachloroethane . 4 The data collected to date suggests that another source of groundwater contamination may exist to the west or southwest of the site We have not made a review of the area to determine if such a source has been identified; that investigation will be made as time allows RECOMMENDATIONS Based upon the data collected to date, we offer the following recommendations . 1 Place the three wells on a quarterly monitoring program This will provide additional information concerning possible other sources & hopefully indicate directions for further investigative work 2 Review existing County EHD files & other sources in an attempt to identify other sites that may be causing, or contributing to, the groundwater contamination encountered beneath the property. • 3 Further investigative work should be deferred until 10