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Site Background Information : Quick N Save #1 Page 6 of 9 Various BTEX compounds were reported in samples collected from borings MWS , MW91 MW10 , EW2 and EW3 at maximum concentrations of 28 mg/kg benzene , 160 mg/kg toluene , 65 mg/kg ethylbenzene , and 316 mg/kg xylenes in sample EW2-40 . Fuel oxygenate MTBE was reported in samples MW9-35 and MW 10-75 at concentrations of 0 . 10 mg/kg and 0 . 015 mg/kg , respectively. TAME was reported in sample MW9-50 at a concentration of 0 .012 mg/kg . Lead scavenger 1 ,2-DCA was reported in samples MW9-50 and EW2-40 at concentrations of 0 . 050 mg/kg and 0 .34 mg/kg , respectively. PILOT TESTS Ground Water Pumping Tests - August 2005 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 draw-down was recorded in observation well MW-4 (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 test was cancelled . Utilizing 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 radius of influence for EW- 1 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 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 fe/day (equivalent to 70 gallons per day/ft) and a storativity value calculated at 0 .00031 . Based on transmissivity values of 10 .6 ft2/day (first stage) and 9 .4 ftZ/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 10° cm/s (second stage). These hydraulic conductivities are consistent with a screened interval located within a silty fine sand . This _ suggests that although the pilot boring for EW- 1 encountered some coarser grained sand , the fine silty sand encountered between 30 and 55 feet bsg in previous pilot borings for MW- 1 through MW-4 is more characteristic of the aquifer (seethe AGE-prepared Quarterly Report - First Quarter 2004, dated 15 June 2004). a Advanced GeoEnvironmental, Inc.