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20 March 2006 AGE-NC Project No. 034071 ;? _ Page 7 of 13 of selected soil samples are summarized in Table 1 . The laboratory reports (CTEL project no. CT214-0508131 ) and chain-of-custody forms are included in Appendix F. 3.0. GROUND WATER AQUIFER PUMPING TEST A variable-rate ground water aquifer pumping test was performed on 29 August 2005, to assess the general ground water aquifer characteristics and to assess aquifer response to ground water extraction. The pumping test consisted of extracting ground water from extraction well EW- 1 utilizing a 4-inch diameter Grundfos Redi-flo pump. Monitoring wells MW- 1 through MW-4 were utilized as observation wells to determine the draw-down radius of influence. Extracted ground water was containerized in an on-site 10,000-gallon steel Baker tank. During the pumping tests, . -inch diameter, model 3001 Solinst Levelogger pressure transducers were deployed in well EW- I , and observation wells MW- 1 through MW-4 to collect draw-down data. Each pressure transducer was preprogrammed prior to the pumping test to log water levels at one-minute intervals; copies of semi-logarithmic plots of draw-down versus time (based on the water level data from the Levelogger, corrected for barometric pressure) from EW- 1 is in Appendix H. Draw down in observation wells MW- 1 through MW-4 was negligible, and therefore not plotted In addition, a Solinst Water Level Indicator was used to manually collected draw-down data from well EW- 1 and observation wells MW- I through MW-4 during the constant-rate pumping test. 3 . 1 . VARIABLE-RATE 'STEP' GROUND WATER PUMPING TEST i On 29 August 2005, the aquifer ` step' draw-down pump test (variable-rate pump test) was performed at the site. The first stage of the pump test consisted of extracting ground water from EW- 1 at a rate of 1 gallon per minute (GPM); the second stage consisted of extracting ground water at a rate of 0 .75 GPM. The pumping rate was decreased during the second stage of pumping due to insufficient well response, and the test was aborted after approximately 4.5 hours. During the first stage of the pump test (pump rate of 1 GPM), the maximum ground water draw-down measured in extraction well EW- 1 was 23 . 12 feet after approximately 60 minutes of pumping operation; the test was paused at this time for approximately 80 minutes to allow the wells to recharge. No significant draw-down was recorded in observation well MW-4 (53 .5 ft away from EW-1 ); MW- I through MW-3 showed very slight draw-downs of between 0.03 and 0.08 ft ( 19.5 to 26 ft away from EW- 1 ). Wt <, F IS G . 1. , During the second stage of the pump test (pump rate at 0.75 GPM), the maximum ground water draw-down measured in well EW- 1 was 19. 53 feet after approximately 125 minutes of pumping Advanced GeoEnvironmental, Inc. �. 7