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I ' 19 December 2005 AGE-NC Project No 99-0645 ' Page 4of8 ' advanced southeast of well MW-2 to 70 feet bsg, boring MW-1R was Installed east of the former UST area to 100 feet bsg, vapor well VW1B was advanced under the building at a 20 degree angle to an extent of 40 feet, VW 1 A was Installed east of the former UST area to 70 feet bsg, V W2 was ' Installed east of the former UST area to 40 feet bsg, and VW3 was Installed south of well MW-3 to 60 feet bsg Soil samples were collected at five foot intervals, generally beginning at 10 feet bsg, or where native soil was encountered below backfill Monitoring and vapor extraction wells were ' completed within the following Intervals MW-IR from 80 feet to 100 feet bsg, V W 1 B from 15 feet to 40 feet bsg, VW 1A from 40 feet to 70 feet bsg,V W2 from 15 feet to 40 feet bsg,and VW3 from 20 feet to 50 feet bsg ' A total of 28 soil samples were analyzed Samples from B6'had concentrations of BTEX compounds and MTBE above laboratory reporting limits MTBE ranged from 0 010 mg/kg to 0 63 mg/kg BTEX ' compounds were detected at maximum concentrations of 0 020 mg/kg benzene, 0 060 mg/kg toluene, 0 030 mg/kg ethylbenzene, and 0 070 mg/kg xylenes The sample results from B7 showed only one contaminated sample, collected at 30 feet bsg, with 0 49 mg/kg MTBE At 40 feet bsg in MW-1 R, 1 2 mg/kg TPH-g was detected, MTBE was detected at concentrations of 0 43 mg/kg and 12 mg/kg at 30 feet and 40 feet, respectively, TAME was detected at 30 feet and 40 feet at concentrations of 0 040 mg/kg and 0 030 mg/kg, respectively ' Results for VW 1 A showed TPH-g and TAME at detected 40 feet bsg at concentrations of 4 6 mg/kg and 0 010 mg/kg, respectively MTBE was detected from 40 feet to 60 feet bsg at concentrations I ranging from 0 030 mg/kg to 4 2 mg/kg Soil from VW3 had detections of MTBE at 30 feet and 40 feet bsg at concentrations of 0 020 mg/kg and 0 060 mg/kg,respectively Analytical results of soil samples are summarized In Table 2 25 SOIL PROFILE ' Based on soil data collected from soil borings B 1 through B7 MW-1 through MW-3 V W 1 through g g � g g VW3, and the UST excavation, the subsurface soil generally consists of clayey silt, silty sand, and silt from surface grade to approximately 17 feet bsg An approximately 10-foot layer of silty sand, poorly graded sand, and gravel was encountered from 17 feet to 32 feet bsg, with clayey silt, silty sand, and silt, Interspersed with discontinuous lenses of sandy material, extending to 75 feet to 80 feet bsg A layer of silty sand and gravel was Identified between 75 feet and 80 feet bsg on the south end of the site and between 80 feet and 85 feet on the north end Clayey silt,silty sand,and silt, interspersed with discontinuous lenses of sandy material, was encountered to the total depth of the borings • ' Advanced CeoEnvironroental,Inc