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4• RESULTS Site Lithology Soils encountered during this investigation consisted primarily of clays, sandy clays, and silts, with intermittent sand stringers occurring primarily at depths greater than twenty feet. Copies of the boring logs for Borings SV1 through SV8 are included in the Appendix A In general, a dark brown clay was encountered to a depth of five feet bgs From a depth of five to twenty feet, soils were primarily silts and clays From twenty to twenty-eight feet, soils consisted of clays, sandy clays, and fine-grained sands There is generally good correlation of silts and clays from one borehole to the next Site Hydrology Depth to water was measured in each of the existing on site monitoring wells on 27 February 1995 These measurements are presented along with previous measure- ments in Table 1 Static groundwater levels have risen approximately two feet from December 1994 to February 1995 Therefore, the soil-groundwater interface, (technically termed the capillary fringe zone) has also risen Depth to water is currently between 24 and 25 feet bgs across the site These are the highest levels recorded on the site since the wells were installed in 1992 The groundwater flow direction continues to be northeasterly, consistent with all other measurements taken at the site A groundwater contour map is presented on Figure 3 Soil Vapor Sampling Results Soil vapor sampling results did not correlate with hydrocarbon concentrations detected in descrete soil samples collected at identical depths The very fine-grained materials (silts and clays) associated with this site may have limited the ability of the sampling equipment to obtain a volume of air large enough to be representative of the sampling depth Because of the poor initial correlation between soil vapor and soil sample analytical results, C14cbsk940548keoattdoc 6 940549 00