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Site Background Information: Quick N Save #1 Page 4 of 5 TPH-g was detected in all analyzed samples from EW- 1 at concentrations between 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 at 25 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 V W-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 VW4 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. GROUND WATER PUMPING TESTS On 29 August 2005, 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 drawdown was recorded in observation well MW-4 (53 . 5 It south of EW- 1 ); MW- 1 through MW-3 showedvery slight draw-downs ofbetween 0 .03 and 0 .08 ft ( 19 .5, 26, and 25 . 5 It 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 ofpumping 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 test was cancelled. Utilizing a semi logarithmic plot of ground water draw-down vs. observation well distance to pumping well (Jacob straight-line method), abest-fit line was utilized to project a radius of influence for EW4 at approximately 29. 8 feet at 1 . 0 GPM. Utilizing the Distance-Drawdown Method (Jacob straight-line method) for the first stage of the pump test (1 .0 GPM), a transmissivity was calculated at 10 . 6 ft2/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 ftZ/day (equivalent to 70 gallons per day/ft) and a storativity value calculated at 0 . 00031 (Appendix J). Based on transmissivity values of 10. 6 WIday (first stage) and 9.4 fe/day (second stage) and an aquifer thickness of 20 ft (screen interval at EW- 1 ), hydraulic conductivity values were calculated at 0 .53 ft/day, or 1 .9 x 104 cm/s (first stage) and 0 .47 ft/day, or 1 .7 x 104 cm/s (second stage) . These hydraulic conductivities are consistent with a screened interval located within a silty fine sand. This Advanced GeoEnvironmental, Inc.