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I ' 130 gallons per day per foot (gpd/ft) The hydraulic conductivity (K) was calculated by dividing the Ts by the aquifer thickness of 17 feet in the extraction well EX-1, where the aquifer thickness equals the thickness of the water column present in the well The ' calculated K ranged from 0 0057 to 0 00036 centimeters per second These hydraulic conductivities are representative of clayey sands, till, silty sands, fine sands and well sorted sands and are fairly consistent with the lithology described in the saturated zone on the boring logs (Attachment C) A summary of hydraulic properties determined during the ' pumping test is presented on Table 6 AQTESOLV output files are provided in Appendix H A theoretical capture zone was calculated for the extraction well EX-1 using the ' transmissivity calculated during the step-drawdown and constant-discharge pumping tests The capture zone is defined by the groundwater streamlines dividing the region producing inflow from the region that does not produce inflow to the extraction well The capture zone 1 is defined by three distances 1)"a" which is parallel to groundwater flow and downgradient of the pumping well (a = Q/2TrTi) where Q equals the pumping rate, T equals the transmissivity and i equals the groundwater gradient, 2) "b" which is perpendicular to groundwater flow from the pumping well to the streamline boundary (b = Q/4Ti), and 3) "c" 1 which is the half-width (radius) of the capture zone upgradient of the pumping well where streamlines are parallel to the groundwater flow direction (Javandel and Tsang 1986) Using the mean of transmissivity of 130 gallons per day per foot (gpolft), the hydraulic gradient of 1 0 005 and discharge rate of 0 8 gpm, the capture zone dimensions are 280 feet-in the "a" direction and 440 feet in the "b" direction The average capture zone for the aquifer was also approximated using the FLOWPATH model to simulate groundwater flow conditions at the site The model incorporated known hydraulic parameters and groundwater elevation data for the aquifer Groundwater 1 extraction at 0 8 gpm from the aquifer was modeled at well EX-1 and the resulting capture zone for that well is defined The results indicate a similar capture zone to that calculated by the Javandel and Tsang (1986) method 1 Groundwater Sample Collection Grab groundwater samples were collected from well EX-1 before and after the steady-state pumping test on August 12 and August 13, 2004 The groundwater samples were submitted 1 to Kiff Analytical for analysis of TPHg, BTEX, MtBE, TBA, DIPE, EtBE, and TAME by EPA Method 82608 1 Laboratory Analytical Results Laboratory analyses of water samples collected before and after the steady-state pumping test are presented in Table 3 TPHg, BTEX, DIPE, ETBE, and TBA were not detected in 1 either water sample at concentrations above laboratory limits MTBE concentration decreased from 7,400 pg/L before the test to 5,400 pg/L after the test TAME also decreased from 22 pg/L before the test to 10 pg/L after the test Certified laboratory 1 analytical data and chain-of-custody documentation are included in Appendix F 1 i 1 32262 Assessment&Feasibility Report&SCM doc 12 September 30 2004 ' 77EL 32262 04 0502