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constituents (cadmium and chrome) which most significantly <br /> exceed MCL' s were both not detected at high levels in soils. <br /> Additionally all of the metals levels, with the exception of <br /> arsenic decreased significantly from well MW1 to MW2 . <br /> Depending upon the groundwater flow direction this could <br /> indicate an off site source for the water contamination, <br /> particularly the chrome, lead and cadmium which are common <br /> paint constituents. The detection of acetone in MW1 could <br /> also be related to an off site source and it is also <br /> typically associated with painting activities. However, <br /> acetone is also used in the laboratory and could represent <br /> contamination during analysis. <br /> As with the soils, the background quality of the shallow <br /> water zone may be poor over a large area and not <br /> attributable to activities at the site. This would require <br /> sampling from a shallow well some distance up-gradient for <br /> comparison. The determination of gradient direction must <br /> first be accomplished by installing a third well at the <br /> site. <br /> 5.0 CONCLUSIONS/RECOMMENDATIONS <br /> It appears likely, although the evidence is not entirely <br /> conclusive, that the subject site has been contaminated by <br /> past land use practices. The possibility exists that <br /> apparent soil contamination may represent unusual background <br /> levels for certain constituents and this should be verified. <br /> Additionally the question of whether the materials are <br /> hazardous based on soluble levels (STLC) should be confirmed <br /> by analyzing extracts from the soil. <br /> The groundwater at the site contains elevated concentrations <br /> of a number of constituents, however the possibility of an <br /> off site source exists. The determination of the direction <br /> of flow is critical and will require at least one additional <br /> well. <br /> To further assess conditions at the site as they relate to <br /> hazardous or designated waste problems we recommend the <br /> following steps: <br /> 1. The collection of 4 soil samples from the site and one <br /> from off site to be analyzed for total and soluble <br /> priority pollutant metals. <br /> 2. The installation of one additional monitoring well to be <br /> sampled for priority pollutant metals and volatile <br /> organics. <br /> 4 <br />