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{� 18 November 2005 AGE-NC Project No 02-0962 Page 5 of 7 TPH-g was detected in the soil samples collected from boring MW-4 at 15 feet bsg(MW4-15) and at 35 feet bsg (MW4-35) at concentrations of 46 milligrams per kilogram (mg/kg) and 230 mg/kg, respectively, TPH-g also was detected in soil samples MW6-30 and MW6-35 at concentrations of 34 mg/kg and 38 mg/kg, respectively TPH-d was detected in soil samples MW4-15, MW4-20, MW4-35, MW6-30, and MW6-35 at a maximum concentration of 2,600 mg/kg in sample MW4-15 MTBE was detected in samples MW4-20 and MW4-25 at concentrations of 0 016 mg/kg and 0 017 mg/kg, respectively No additional analytes were detected at or above laboratory detection limits in the soil samples analyzed Figures 6,7,and 8 illustrate the vertical extent of adsorbed petroleum hydrocarbons at the site Analytical results of soil samples are summarized in Table 2 The laboratory report (CTEL Project No CT214-0508008),quality assurance and quality control(QA/QC)reports, and chain of custody forms are included in Appendix G {. 3 3 GROUND WATER GRADIENT AND FLOW DIRECTION The elevation of ground water in each of the monitoring wells was calculated by subtracting the depths to ground water from the surveyed relative casing elevations (Table 1) Depths to ground water ranged from 19 63 feet (MW-1) to 19 88 feet (MW-2) below the tops of the well casings Ground water elevation at the site averaged approximately 7 79 feet below MSL, indicating a decrease in ground water elevation of 1 46 feet since the last ground water monitoring event in May 2005 During the September 2005 ground water monitoring event,ground water was inferred to be flowing radially outward from a ground water ridge centered over well MW-6 under a uniform hydraulic gradient of approximately 0 001 foot/foot (ft/ft) During this monitoring event, ground water elevations were within the screened intervals of the wells, indicating that the wells are properly screened to yield samples representative of shallow groundwater conditions Figure 9 illustrates the contoured ground water elevation as measured on 01 September 2005 34 ANALYTICAL RESULTS OF GROUND WATER SAMPLES TPH-g and MTBE were detected in the ground water sample collected from well MW-4 at equivalent concentrations of 120 micrograms per liter(µg11) .1 Advanced GeoEnvironmental,Inc