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GeoHydrologic Consultants, Inc recycled/disposed Drawdown and recovery was measured and recorded at regular ' intervals throughout the test from the pumping well EW-5S and drawdown was measured in observation wells EW-513, MW-4, TB-10, and TB-7 Groundwater levels measured in the observation wells exhibited a steady rise to all observation wells throughout the 12- hour test This may be attributed to the low groundwater extraction rate sustainable to EW-5S (approximately 0 25 gpm) coupled with changes in atmospheric pressure and adjustment of the aquifer to these changes once the well lids were opened The rise in water levels measured in EW-5D was 0 15 feet at the end of the test, the rise measured to MW-4 was 0 17 feet, the rise measured to TB-10 was 0 15 feet, and the rise measured in TB-7 was 0 16 feet Since only a rise in water levels was observed throughout the test, ' drawdown data from the wells could not be used for pumping test analysis Figure 7A illustrates the drawdown graph for pumping well EW-5S and Figure 7B illustrates the recovery graph for the pumping well EW-5S The drawdown and recovery data for this well is summarized in Table 10B and copies of field data are included in Appendix D ' Analysts of drawdown data for EW-5S is presented in the following Table 7 4-1 and the analysts of recovery data is presented to the following Table 7 4-2 An estimated ' saturated thickness of 40 feet was assumed from the well depth, static groundwater level the day of the pumping test, the ltthologtc logs for the Site, and its proximity to EW-5D, which, as a nearby deep well had an assumed saturated thickness of 40 feet According to ' Todd (1980), hydraulic conductivities to this range are representative of soils consisting of silt/clay, which is representative of the sediment described to the boring log for EW- 5S It should be noted that if vertically thinner saturated thicknesses were assumed, the ' calculated hydraulic conductivity would increase accordingly Table 7.4-1 Pumping Test Results for Drawdown EW-5S rAquifer Parameters Pumping ' Transmisstvtty (ft2/day) 4 38 ds = 2 00 ' Hydraulic Conductivity (ft/day) 0 110 Groundwater Velocity (ft/day) 0 0014 Stagnation Point (ft) 448 I 'roc 171 Pilot Study Page 22