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15 June 2004 AGE-NC Project No 01-0877 Page 5 of 7 6 feet bsg Between 12 feet bsg and 50 feet bsg, the soil consisted of light brown to yellow/orange- brown clayey sands and silty sands, with the exception of a blue gray to brown clay to sandy clay layer at between approximately 23 feet bsg to 27 feet bsg From approximately 50 feet bsg to total depth of boring B5, the soil consisted of a gray, well graded medium to coarse sand with gravel Lines of cross section are illustrated on Figure 2, stratigraphic cross sections are depicted in Figures 3 and 4, and the soil boring logs are provided in Appendix B IIn general, strong hydrocarbon-like odors were detected in soil samples collected below 15 feet bsg from each boring In addition, measurable organic vapors were detected in all soil samples at concentrations ranging between 4 4 parts per million (ppm) to above the detection limit of the PID unit (Appendix B) ' 32 ANALYTICAL RESULTS OF SOIL SAMPLES ' Nineteen soil samples were analyzed-for the constituents listed in section 3 3 (Table 2) The following constituents were detected at or above laboratory detection limits TPH-g was detected in twelve of the soil samples at concentrations ranging between 1 3 milligrams per kilogram(mg/kg)in sample MW4-30 and 2,200 mg/kg in sample MW3-30,TPH-d was detected ' in four samples at concentrations ranging from 20 mg/kg (B5-24) to 200 mg/kg (MW4-40), and TPH-mo was detected in one sample at a concentration of 870 mg/kg (MW3-30) ' One or more BTEX compounds were detected in samples collected from borings MW 1 through MW4 and B5, the maximum concentrations were detected froin sample MW3-30 at 11 mg/kg benzene, 79 mg/kg toluene, 33 mg/kg ethylbenzene and 128 mg/kg total xylenes INo additional target analytes were detected at or above laboratory detection limits in the samples analyzed Hydrocarbon impact to soil is shown in Figures 5 and 6 with an approximation of the ' extent of contamination Analytical results of soil samples are summarized in Table 2 The laboratory reports (CTEL Project No CT214-0309054 and CT214-0309175), quality assurance and quality control (QA/QC) report and chain-of-custody forms are included in Appendix F I ' 3 3 GROUND WATER GRADIENT AND FLOW DIRECTION ' At the time of the October 2003 sampling event, depths to ground water ranged from 27 04 feet to 27 76 feet below the tops of the well casings The average ground water elevation at the site was ' approximately 17 35 feet below MSL(Table 1) Ground water flow was inferred to be towards the northeast under a gradient of approximately 0 003 foot/foot (Figure 7) Advanced GeoEnvironmental,Inc I ,