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I <br /> 20 March 1996 <br /> IAGE-NC Project No 95-0139 <br /> Page 4 of 6 <br /> probings B5 and B9,beginning at a depth of 10 feet in probings B7 and B8, and beginning at a depth <br /> of 11 feet in probing B6 All samples were collected using a Geoprobe soil sampling assembly and <br /> four brass sleeves After collection, the ends of the'second brass sleeve were covered with Teflon' <br /> sheets, capped and sealed with tape Samples were placed in a chilled container and transported to <br /> McCampbell Analytical, Inc (MAI) under chain-of-custody procedures <br /> One grab ground water sample was collected from probing B9 using a Geoprobe water sampling <br /> assembly The sample was collected in 40-ml VOA vials and a 1-liter amber bottle, placed in a chilled <br /> container and transported under chain-of-custody procedure to MAI <br /> Soil and ground water samples were analyzed for TPH=g, TPH-d and BTE&X in accordance with <br /> EPA methods 8015m/5030 and 80201602, respectively <br /> E3 4 LOGGING <br /> Soil was extruded from the remaining brass sleeves and screened for the presence of organic vapors <br /> using a photo-ionization detector (PID Thermo Environmental 580A, 10 OeV, calibrated to <br /> isobutylene), and the readings were recorded on the boring logs Soil was described in accordance <br /> with the Unified Soil Classification System (see Boring Logs, Appendix C) <br /> 4.0.i FINDINGS <br /> 4 1 GROUND WATER GRADIENT AND DIRECTION <br /> The relative elevation of ground water in each well was calculated by subtracting the ground water <br /> depth from the surveyed casing elevation (Table 1) Depth to ground water at the site ranges from <br /> 8 73 to 1126 feet Ground water rose an average of 0 41 feet between the June 1995 and January <br /> 1996 monitoring events <br /> The ground water flow direction continues to be north to northwest The gradient steepens from. <br /> approximately 0 002 ft/ft over the southern portion of the site to approximately 0 004 ft/ft in the <br /> northern portion of the site (Figure 3) The gradient and flow direction are nearly identical to those <br /> measured during the June 1995 monitoring event <br /> 1 4 2 LABORATORY ANALYSIS OF GROUND WATER SAMPLES <br /> TPH-g and TPH-d were detected in MW-1 at concentrations of 3,700 and 1,800 ppb, respectively <br /> BTE&X were also detected in this sainple at concentrations ranging from 4 8 ppb (toluene) to 380 <br />