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•) ar1 pumping an extraction well at a constant rate, I GPM, 2 GPM, and 3 GPM, for various time periods, I month, 1 year, and 2 years, for various distances from the extraction well were calculated (Walton, 1962). The results are presented on Tables I through 9 The zone of plume capture of a pumping well can be calculated using the natural groundwater velocity gradient and the velocity gradient induced by pumping Up gradient of the well the natural gradient and the gradient caused by pumping combine to move water toward the well Down gradient of the well, the natural ground-water flow acts against the force created by pumping The point down gradient where the pull of water back-to the well is countered by the flow away from the well due to the natural velocity is termed the velocity divide The distance to the velocity divide can be calculated using the s values at various distances from the well, and the natural ground-water gradient Using the s values calculated with a pumping rate of 3 GPM, a time frame of two years and an estimated gradient of 1445, the distance to the velocity divide ranges from 100 to 150 feet These calculations and the drawdown observed in the on site wells during the pumping test indicate that pumping from well EW-1 might provide sufficient coverage and capture of the dissolved product plume 4.0 CONCLUSIONS Based on the MW-13 slug test data, the hydraulic conductivity may vary between the wells on site and MW-13 area `'Vater may move more easily through the aquifer in the area of the on site wells than it does in the area of MW-13 Based on available step test data a pumping rate up to 3 GPM could be sustained in extraction well EW-1 The 24 hour aquifer test was used to calculate values of T and S for the site The calculated T and S values were used to produce theoretical drawdown estimates, which in turn were used to calculate the potential velocity divides under various pumping rate and duration scenarios Using the estimated gradient at the site and pumping at 3 GPM for 2 years from a theoretical extraction well at the location of EW-1 might produce a velocity divide between 100 and 150 feet down gradient of the well Based on the estimated groundwater plume geometnes for the chemicals detected in the groundwater at the site, a pumping well at the location of EW-1 pumped at 3 GPM for 2 years might provide sufficient coverage to capture and contain the dissolved product plume A.&&. , 4 Q.n..y R.P*"%a.33 QEWQrr[.S