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I' 09 April 2002 AGE-NC Project No 98-0497 Page 5 of 6 1 #179 at 25 86 feet above mean sea level (MSL) The results of the monitoring well survey are contained in Table 2 The surveying report is presented in Appendix D 4.0. FINDINGS ' Boring logs were utilized to model the subsurface soil profile at the site Ground water elevations were determined from field data collected on 18 February 2002 The hydrocarbon-impact to soil was inferred from laboratory analysis of soil samples and field observations 41 SOIL PROFILE Generally, clay, clayey silt, silty clay, silt, sandy silt, silty sand and poorly graded sand were encountered in each of the borings at various depths Approximately 75% of the soils encounterd during the investigation were composed primarily of fine-grained material including sandy silt, silt and clayey silt, silty clay and clay, coarse-grained soils were encountered in thin intervals . (approximately 5 to 15 feet thick) Boring logs are included in Appendix B Based on the boring logs recorded during this and previous investigations, cross sections A-A' and 1 B-B'were constructed depicting the general soil profile beneath the site(Figures 3 and 4) The upper 50 feet of soil is composed predominantly of sand,with several thick, laterally discontinuous clay lenses towards the north, east and west Beneath the sand layer is a 20-to 30-foot thick clay layer Underlying the clay layer is an interval apparently composed of sands and gravelly sands (based on boring P-3 soil data) 4 2 GROUND WATER ELEVATION The elevation of ground water in each well was calculated by subtracting the depth to ground water from the surveyed well casing elevations (Table 2) 1 The depth to ground water was 6123 feet and 59 98 feet below the tops of the well casings in MW-4 and MW-5, respectively Ground water elevations at the site were 35 72 feet below MSL in well MW-4 and 35 74 feet below MSL in well MW-5 • ' Advanced GeoEnvirenmental,ine