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20 March 2006 AGE-NC Project No. 03- 1071 Page 12 of 13 12 milligrams per kilogram (mg/kg) at 30 feet, and 2,600 mg/kg at 40 feet. TPH-g was detected in VW-4 at a depth of 25 feet and at a concentration of 1 .5 mg/kg. • BTEX compounds were detected in all three soil samples from EW- 1 ; maximum concentrations were detected in the sample collected at 40 feet. Benzene was detected at a maximum concentration of 16 mg/kg; toluene at 66 mg/kg; ethylbenzene at25 mg/kg; xylene at 128 mg/kg. Benzene was detected in VW-3 at 35 feet at a concentration of 0.03 mg/kg. Ethylbenzene was detected in VW-3 at 25 feet and VW-4 at 25 feet, at concentrations of 0 .014 and 0.013 mg/kg, respectively. Xylenes were detected in VW-3 at 25 feet and VW-4 at 25 at concentrations of 0.028 and 0.024 mg/kg, respectively. • MTBE was detected in the sample collected from EW- 1 at 30 feet only, at a concentration of 0 .78 mg/kg. MTBE was detected in seven out of the nine samples from VW- 1 through VW-4, at a maximum concentration of 0.31 mg/kg in VW- 1 at 35 feet bsg. 1 ,2-DCA was detected in all three samples from EW- 1 , at a maximum concentration of 1 .2 mg/kg in the sample from 40 feet. No other constituents of concern were detected from the laboratory analysis • On 29 August, a variable rate ground water pumping test was conducted. During the test, maximum ground water draw-down during the first stage of the pump test (pump rate of 1 GPM) measured in extraction well EW- 1 was 23 . 12 feet after approximately 60 minutes of pumping operation; no significant draw-down was recorded in observation well MW4 (53 .5 ft south of EW- 1); MW- 1 through MW-3 showed very slight draw-downs of between 0.03 and 0 .08 ft (19.5 , 26, and 25.5 ft west, north, and east of EW- 1 , respectively). Observed draw downs during the second stage of the pump test (pump rate at 0.75 GPM) were similar: the maximum ground water draw-down measured in well EW- 1 was 19.53 feet after approximately 125 minutes of pumping operation (after the restart); no significant draw-down was recorded in observation well MW-4; MW- 1 through MW-3 showed very slight draw-downs of between 0.02 and 0.04. • Due to the results of the 8-hour variable rate pump test, the proposed 24-hour constant rate i test was cancelled. • Utilizing the time limited data a semi-logarithmic plot of ground water draw-down vs. observation well distance to pumping well (Jacob straight-line method), a best-fit line was utilized to project a theoretical radius of influence for EW- 1 at approximately 29.8 feet at 1 .0 GPM (Appendix H) . However, no observable or re-measurable drawdown was shown in the field at the designated observation wells. • Utilizing the Distance-Drawdown Method (Jacob straight-line method) for the limited duration of the first stage of the pump test (1 .0 GPM), a transmissivity was calculated at 10.6 ftZ/day (equivalent to 79. 1 gallons per day/ft) and a storativity value calculated at 0 .0012 . For the second stage of the pump test (0 .75 GPM), a transmissivity was calculated at 9.4 ft'/day Advanced GeoEnvironmental, Inc. /