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' 30 May 2001 AGE-NC Project No 95-0128 ' Page 4 of 6 ' 4-inch diameter submersible Grundfos Redi-flo pump The pumping rate was determined by measuring the time required to fill a 5-gallon bucket from the pump discharge hose ' The pump test utilized '/a-inch diameter, model 3001 Sohnst Levelogger pressure transducers that were deployed in —ells MW-4, MW-5 and EW-1 Each pressure transducer was preprogrammed prior to the pumping test to log water levels at one-minute intervals Copies of pressure transducer ' water level data logged from MW-4, MW-5 and EW-1 are in Appendices C, D, and E, respectively The depth to ground water was measured with a Solinst water meter in observation wells MW-1, ' MW-2, MW-4, MW-5 and MW-6 and vapor well VW-1 (Appendix C) Semi-logarithmic plots of draw-down versus time for MW-4, MW-5 and EW-1 are in Appendix F ' After 700 minutes of constant rate pumping (5 GPM), the maximum ground water drawn-down in extraction well EW-1 was observed to be 11 15 feet (Appendix C) Maximum draw-down in well MW-5 (located 15 feet toward the northeast) was 1 1 feet (Appendix D) Draw-down in well MW-6 ' (located approximately 50 feet toward the west) was 0 12 feet (Appendix E), draw-down in well MW-4(located 60 feet towards the southeast) was 0 1 feet and was observed in vapor extraction well VW-1 (located approximately 60 feet towards the southwest) at 0 06 feet (Appendix C) IThe maximum ground water draw-down in observation wells MW-4, MW-5, MW-6 and vapor well VW-1 versus the distance of each well from the extraction point was graphed on semi-loganthmic ' paper, utilizing the Distance-Drawdown Method, a general value of the transmissivity, storativity and hydraulic conductivity of the aquifer were determined (Appendix G) ' Utilizing the data collected and plotted, a transmissivity value of 205 ft'/day or 1,536 gallon/day/feet, a storativity value of 0 054, a hydraulic conductivity value of 0 022 cm/s was calculated A radius of influence was projected at 65 feet utilizing a semi-logarithmic plot of draw-down versus distance ' (Appendix H) Results of the aquifer ground water pumping test are summanzed in Table 1, a site plan depicting the observed radius of influence during the 27 March 2001 pumping test is depicted in Figure 3 32 EXTRACTED WATER SAMPLING PROCEDURES Approximately 5,000 gallons of purged water were generated during the pump test During the pump test, three sets of a grab samples were collected prior to discharge into the tank utilizing three 40-m1 EPA-approved volatile organic analysis (VOA) vials containing 0 5 ml 18% hydrochloric acid as a sample preservative The three samples were rnlected at 12 30 prn (4. hour), 4 30 pm (8 hours) and at the termination of the test 8 30 pm (12 hours) Following sample collection, each preserved sample was logged on a chain-of-custody form, placed IAdvanced GeoEnvironmentai Inc I