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06/24/2002 15 42 2094671118 AGE STOCKTON PAGE 05 . 31 January 2002 AGE-NC Pi olect No 95-0128 Page 4 of 8 The pump test consisted of extracting gi ound water from well EW-1 at a rate of 5 GPM utilizing a 4-inch diameter submersible Grundfos Redi-flo pump The pumping rate was determined by measuring the time requii ed to fill a 5-gallon bucket fi om the pump discharge hose The pump test utilized 7/a-inch diameter, model 3001 Solinst Levelogger pressure transducers that were deployed in wells VW-3,VW-4 and VW-I Each pi essure transducer was preprogrammed prior to the pumping test to log water levels at vile-minute intervals However,no data was recorded from within vapor well VW-1,due to an unanticipated and excessive di awdown of the water level in vapor well VW-I Copies of pressure transducei water level data logged are m Appendices C The depth to ground water was also manually measured with a Solinst water meter in extraction well EW-1 and observation wells EW-2, MW-3, MW-4, MW-5, and MW-6 and vapor well VW-1 to VW-4 (Appendix D) Semi-logarithmic plots of draw-down vei sus time for observation wells are m Appendix E ,A.ftei 720 minutes of constant late pumping (5 GPM), the maximum ground water drawn-down in extraction well EW-I was observed to be 8 4 feet Maximum draw-down in well VW-I (located equi- . gradient 5 feet towai d the west) was 1 2 feet Di aw-down in well EW-2 (located approximately down-gi adient 15 feet towai d the east) was 0 55 feet, draw-down in well VW-2- (located equi- gradient 22 feet towards the northeast) was 0 89 feet, draw-down in well VW-3 (located down- gradient 25 feet towai ds the east)was 0 8 feet,di aw-down in well VW-4(located up-gradient 30 feet towards the west) was 0 5 feet, drawdown was observed in well MW-3 (located equi-gradient approximately 25 feet towai ds the northwest)at 0 41 feet, draw-down in well MW-5(located down- gradient 60 feet towai ds the east) was 0 23 feet and was observed in well MW-4 (located down- gradient approximately 70 feet towai ds the northeast) at 0 23 feet (Appendix D) Results of the aquifei ground water extraction test are summarized in Table 1 An inflection of the ti end of the drawdown vs time plots at approximately 250 imiiutes suggests initiation of turbulent flow tnto the extraction well with loss ofwell 4ARciency Steady state conditions may not have been achieved at the pumping rate The maximum gi ound water draw-down in obseivation wells versus the distance of each well from the extraction point was graphed on semi-logarithmic paper, utilizing the Distance-Drawdown Method, genei al values for the transmissivity, storativity and hydraulic conductivity of the aquifer were detemnined (Appendix 1~) Utilizing the data collected and plotted, a transtmssivity value of 380 fta/day or 2,840 gallon/day/feet, a storativity value of 0 043, a hydi aulic conductivity value of 94 feet/day or 0 033 cm/s was calculated A calculation of the plume capture zone is included in Appendix G 4dvanced GeoEuvtronmental inc