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04 November 2008 <br />AGE-NC Project No. 02-0926 <br />Page 4 of 5 <br />3.0. FINDINGS <br />Soil stratigraphy was determined from field dated collected during advancement of the monitoring <br />well pilot soil boring. Hydrocarbon impact to soil was assessed by laboratory analysis of soil <br />samples. Soil descriptions from borings MW-4 through MW-6 were integrated with previous <br />subsurface soil descriptions to construct cross-section B-B'. The geologic cross-section B-B' is <br />illustrated in Figure 3. <br />3.1. STRATIGRAPHY <br />In general, brown, gray-brown, and red-brown silts and clays were encountered from approximately <br />5 feet and 45 feet bsg and 55 feet to 65 feet bsg; characteristically, the clay material had moderate <br />plasticity and consistency. Poorly graded or silty sand lenses were identified from 45 feet to above <br />50 feet bsg and 65 to 75 feet bsg, with grain size generally decreasing with depth. Soil boring logs <br />are provided in Appendix B; geologic cross-sections B-B' is illustrated on Figure 3. <br />3.2. ANALYTICAL RESULTS OF SOIL SAMPLES <br />A total of thirty-three soil samples were analyzed for the constituents listed in Sections 2.1. <br />TPH-g , TPH-d, and one or more BTEX compounds were reported in all soil samples collected from <br />boring MW5 except MW5-5 and MW5-10 at maximum concentrations of 3,900 milligrams per <br />kilogram (mg/kg) TPH-g (MW5-15), 330 mg/kg TPH-d (MW5-15), 14 mg/kg benzene (MW5-40), <br />230 mg/kg toluene (MW5-45), 78 mg/kg ethylbenzene (MW5-15), and 690 mg/kg total xylenes <br />(MW5-15). <br />TPH-g and one or more BTEX compounds were reported in soil samples collected from MW6-5, <br />-35,-40-45,-50,-55, and -60 at maximum concentrations of 2,000 mg/kg TPH-g, 3.2 mg/kg, benzene, <br />52 mg/kg toluene, 39 mg/kg ethylbenzene, and 273 mg/kg total xylenes, in sample MW6-40. TPH-d <br />was reported in samples collected from MW6-35,-40,-45,-55, and -60 at a maximum concentration <br />of 230 mg/kg in sample MW6-40. <br />Soil samples collected from boring VW2-10 and VW2-5 reported TPH-g at a maximum <br />concentration of 6.6 mg/kg in sample VW2-10. One or more BTEX compound were reported in soil <br />sampled collected from VW2-10, -15, and -20 at maximum concentrations of 0.048 mg/kg benzene <br />(VW2-10), 0.22 mg/kg toluene (VW-10), 0.064 mg/kg ethylbenzene (W2-20), and 0.680 mg/kg <br />total xylenes (VW2-15). <br />Advanced GeoEnvironmental, Inc.