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f 02 February 2004 AGE-NC Project No 99-0624 ' Page 5 of 8 , ' f 3.0 FINDINGS The soil stratigraphy, ground water elevation, flow direction, and gradient were determined from ' field data The contaminant impact to soil and ground water was quantified by the laboratory analytical data 31 STRATIGRAPHY ' Gray to reddish brown silty sand and fine-grained sand were encountered from 15 feet to approximately 60 feet bsg in boring MW-6, brown,poorly-graded sand was recovered from 60 and 65 feet bsg Pale brown to reddish brown silt with sand was encountered at 30 feet and 70 feet bsg ' in boring MW-7, gray to reddish brown silty sand and poorly graded fine sand were recovered at all other sampling depths ' Organic vapor was detected above 200 ppm in soil samples collected between 15 feet and 30 feet bsg in boring MW-6 and at 45 feet and 50 feet bsg in boring MW-7 Hydrocarbon-like odor was • detected in the same soil samples and in the sample collected at 50 feet bsg from boring MW-7 ' Lines of cross section are illustrated on Figure 2 and stratigraphic cross sections are depicted in Figures 3 and 4 The soil boring logs are provided in Appendix A 1 32 ANALYTICAL RESULTS OF SOIL SAMPLES ' A total of nine soil samples were analyzed for the constituents listed in Section 2 1 4 TPH-g was detected in the soil samples collected from 25 feet bsg in boring MW-6 and from 50 feet bsg in ' boring MW-7, at concentrations of 3 0 mg/kg and 12 mg/kg, respectively MTBE was detected by EPA method 8260 in the soil samples collected from 50 feet, 70 feet, 80 feet and 90 feet bsg in boring MW-7, at concentrations of 28 mg/kg, 2 1 mg/kg, 0 022 mg/kg and 0 086'mg/kg, ' respectively TAME was detected in the soil samples collected at 50 feet and 70 feet bsg in boring MW-7 at concentrations of 0 11 mg/kg and 0 011 mg/kg,respectively TBA was detected in the soil sample collected from 50 feet bsg in bonng MW-7 at a concentration of 2 9 mg/kg No other analytes were detected at or above laboratory reporting limits in the soil samples Cross sections illustrating the extent of impacted soil are depicted in Figures 5 and 6 Analytical results of soil samples are summarized on Table 3 and historical analytical results of soil samples are summarized on Table 4 The laboratory reports (CAL Reference No 5916), quality assurance and quality control (QA/QC) report and chain-of-custody forms are included in IAppendix E Advanced GeoEnvironmental,Inc