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1 <br /> In summary, by placing the borings using the HNU screening <br /> instrument for guidance , the boundaries of the contamination <br /> presence were defined. <br /> Vertical Extent of Contamination <br /> Since samples were collected continuously as the boring <br /> advanced, the vertical extents of contamination with respect to <br />' the ground surface were, to some extent, established. B-4 (p) was <br /> extended to the greatest depth below the surface. This boring , <br /> - and subsequent borings indicated that the contamination presence <br /> extended into the saturated zone (water table) of the proDect <br /> site. <br /> Because of this indication, two wells were emplaced to <br /> _ evaluate the condition of the groundwater at the proDect site. <br /> Since an old gas station exists upgradient, a well was placed in <br /> rboring B-12 to evaluate the condition of the groundwater <br /> sufficiently upgradient from the site's UST installation. The <br /> laboratory analysis of the water samples from MW-2, the <br /> upgradient wells , indicated no contaminant presence. <br /> To then evaluate the effect of the plume on the groundwater, <br /> a monitoring well was installed in an otherwise "clean" boring at <br /> the downgradient edge of the plume. Water samples collected from <br /> r this well (MW-1 ) indicated contamination well in excess of the <br /> i <br /> applicable regulatory limits. An additional water sample was <br /> collected from one of the open "hot" borings prior to <br /> backfilling. This sample also indicated an elevated level of <br />' contamination in excess of the regulatory limits. Additionally, <br /> this "hot" boring also indicated levels of contamination above <br /> Page 36 <br /> 73 <br />