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:MXAffMY <br /> Working To Restore Nature <br /> 5.2.2 Step Drawdown Test <br /> Three short term constant rate tests were conducted on well MW-4 at 0 5, 1 and 3 gallons per <br /> minute (gpm). The pumping rates were chosen based upon a maximum pump capability of <br /> approximately 3 to 4 gpm in the two-inch diameter well The pumping duration for each test <br /> was 30 minutes. The well was allowed to recover completely between each test. <br /> The drawdown after 30 minutes for each of these tests was used to calculate well productivity, <br /> or specific capacity, in gallons per minute per foot of drawdown (gpm/ft). The reciprocal of <br /> specific capacity, specific drawdown (ft/gpm), was then plotted against pumping rate in gpm in <br /> order to evaluate well performance The plot of the data is presented in Appendix II. <br /> The drawdown in a pumped well consists of two components, aquifer losses and well losses <br /> The aquifer losses are primarily related to laminar flow conditions and vary linearly with the <br /> pumping rate. The well losses include head loss which varies both linearly and non-linearly with <br />. pumping rate. The non-linear losses are related to turbulent flow within the well screen, filter <br /> pack and formation. These two components can be characterized by the following equation: <br /> 1 <br /> s = BQ + CQ2 <br /> ' where: <br /> 1 s drawdown at a given time in feet <br /> Q pumping rate in gpm <br /> BQ = linear head loss term (B is a constant) <br /> CQ2 — non linear head loss term (C is a constant) <br /> rearranging terms: <br /> ' s/ <br /> Q = B + C Q <br /> This latter equation represents a straight line on a plot of s/Q versus Q with the Y-axis intercept <br /> corresponding to the constant B and the slope of the line representing the constant C. In this <br /> way, the relative contribution of linear and non-linear head loss can be estimated The non- <br /> 150038MUORMCAP-0794 DRF 6 <br />