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�f 11 analysis for TPHg, BTEX, and oxygenates. REPORT OF FINDINGS FOR THE EXTRACTION WELL PUMP TEST Procedure The influence of the EW-1 was tested on June 25,2004. EW-1 was pumped for 7 hours. The initial flow rate was 17.8gpm,decreasing to 14gpm over the 7 hour period. EW-1 is constructed of 6"PVC well casing in a 15" augured hole with filter pack. The depth of the well is 60' below the ground. The water level is 33' below the ground. The log of borings indicate that the depth of the aquifer is about 53' from the ground surface. The depth of the aquifer is bounded by the free surface of the water at the top and the layer of silts and clays at the bottom, making the aquifer 20' thick. EW-1 is a fully penetrating well. The monitoring wells are 2"PVC casings and vary in depth from 55'to 64.33'. All monitoring wells are considered fully penetrating. The submersible pump was a Grunfos SQ/SQE 180. The flow was tuned with a PVC gate valve and the flow was measured with a 314" flow meter. The contaminated water was pumped through a single pass activated carbon filter that removed the old gasoline and the treated water was stored in one batch in a 21,000gal Rain for Rent tank on the property. The water in the tank will be tested and disposed of through a city sewer discharge permit. The barrels from previous testing and well purging were also pumped through the filters in order to treat and dispose of the 18 accumulated barrels. Depth to ground water data was collected throughout the pumping period and the time interval was noted for each measurement. The time interval for the flows were also noted. The results were analyzed with the AQTESOLV computer program using the Theis confined Aquifer model. The assigned parameters were b= aquifer thickness of 20ft, Kz/Ki= ratio of vertical permeability to horizontal permeability of .5, and that the extraction well and the monitoring wells were fully penetrating. Findings The cone of influence for the 7 hour pump test is as follows: WELL # DISPLACEMENT ft RADIUS ft MW-1 1.15 23.33 MW-2 3.27 41 MW-3 1.35 64.78 MW-7S .45 88 MW-8S .25 143.4 From the computer analysis the Transmissivity is estimated at 0.3621 ft2/min,the Storage coefficient is 0.005304, and the thickness of the aquifer is 20'. • From the outlet of the filter,the treated water analysis was non-detect for all BTEX compounds and 4