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GeoHydrologic Consultants, Inc . Table 7 2-3 Pumping Test Results for Drawdown TB-10 Aquifer Parameters Pumping ' Transmissivity(ft2/day) 1,150 ds= 0 07 Hydraulic Conductivity (ft/day) 2875 Storativity ----6-034 ' Groundwater Velocity (ftJday) 037 ' Stagnation Point (ft) 1635 7.3 Groundwater Results ' The analytical results for the groundwater samples collected at beginning and at the end of the pump test from EW-5D are summarized in Table 9 Laboratory reports and chain- of-custody hain- ofcustody documentation are included in Appendix F ' The sample results indicated that moderate to high concentrations of TPHg and BTEX were detected Concentration for TPHg in groundwater at the beginning of the test was ' recorded to be 67,600 gg/L and at the end of the test it was 96,900 gg/L A similar increasing trend was observed for benzene (2,950 gg/L to 5,340 gg/L), toluene (8,250 gg/L to 16,200 gg/L), ethylbenzene (1,920 gg/L to 2,640 gg/L), and xylenes (11,200 ' µg/l_to 15,200 gg/L) MTBE on the other hand was not detected above the Iaboratory MDL of 0 18 gg/L in both samples 7.4 Pumping Well EW-5S Groundwater extract i on/mon iton ng well EW-5S is a 4-inch diameter well that is installed ' to a depth of 60 feet bgs, with 0 010-inch slotted well screen from 40-60 feet bgs The sand pack extends approximately two feet above the top of screen Groundwater appears to be present under unconfined water-table conditions Static groundwater was measured ' prior to conducting the pumping test in EW-5S at a depth of 47 05 feet bgs, indicating an estimated aquifer thickness of approximately 40 feet ' The pumping test was started at 6 50 AM on April 6, 2005 and was maintained at a constant pumping rate of approximately 0 25 gallons per minute (gpm) for 730 minutes, terminating at 7 00 PM that evening, with a maximum drawdown of 5 80 feet in EW-5S ' at the end of the test A total of approximately 135 gallons of water was removed during the pumping test and stored onsite in a 4,000-gallon polyethylene Baker Tank All water . generated during the test was vacuum trucked from the tank and properly I TQC 171 Pdot Study Page 21