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HydroGeo Consultants 5.2 Pumping Well MW-5 ' P 9 MW-5 is a 2-mch diameter well that is installed to a depth of 90 feet below grade, with ' 0 020-inch slotted well screen from 20 feet below grade to the wells total depth of 90 feet below grade The sand pack extends approximately three feet above the top of screen, an t estimated depth of 17 feet below grade, to the bottom of the borehole at 90 feet below grade The bottom of the well was measured in the field at a depth of 82 18 feet below grade and the well was most likely filled with silt from 82 18 feet below grade to the well total depth Although there is a noticeably more permeable zone of sand and silty sand at a depth of 65 to 70 below grade, this zone did not contain water when this well was installed Groundwater appears to be present under unconfined water-table conditions , Static groundwater was measured prior to conducting the pumping test in MW-5 at a depth of 42 24 feet below grade, indicating an estimated aquifer thickness of 40 feet The pumping test was started at 11 30 on March 16, 2002 and was maintained at a ' constant pumping rate of approximately 1 5 to 1 6 gallons per minute (gpm) for 1,429 minutes, terminating at 11 19 on March 17, 2002 A total of 2,040 gallons of water was ' removed during the pumping test and stored onsite in 34 DOT approved drums awaiting proper disposal The recovery was monitored and recorded however the discharge hose drained back down the well since the pump apparently did not contain a check valve, thus , making the recovery data at the beginning of the test unusable The drawdown was measured and recorded at regular intervals throughout the test from the pumping well MW-5 A petroleum sheen was noted on the pump discharge hose at the completion of the test, however no measurable free product was present in the well or observed in the pump discharge during the test Figure 5 and 6 illustrates the drawdown and recovery graphs for the pumping well MW- , 5 The drawdown and recovery data for this well are summarized in Tables 4 and 5, respectively, and copies of field data are included in Appendix A , Analysis of drawdown and recovery data for MW-5 is presented in the following Table 1 An estimated saturated thickness of 40 feet was assumed from the well depth, static ' groundwater level the day of the pumping test, and the lithologic logs for the Site According to Todd (1980), hydraulic conductivities in this range are representative of soils consisting of fine grained sand to silt, which is representative of the sediment , described in the boring log for MW-5 It should be noted that if thicker saturated thicknesses were assumed, the calculated hydraulic conductivity would decrease accordingly , 1 Page 8 TOC H171 Aquifer Test and RAP Rpt '