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r.. <br /> RecoveKY Test Anal ses <br /> Recovery data were analyzed using the following method as <br /> described by Todd, 1980. <br /> If a well is pumped for a known period of time and then <br /> shut down, the drawdown thereafter will be identically the <br /> same as if the discharge had been continued and a <br /> hypothetical recharge well with the same flow were <br /> superposed on the discharging well at the instant the <br /> discharge is shut down. <br /> 5' = Q <br /> — [W(u) -- W(u') ) (4.47) <br /> 4rT <br /> where <br /> U r2s r2S <br /> — and u' _ --- (4.45) <br /> 4Tt 4Tt' <br /> S' W 2.300 t <br /> log — (4.47) <br /> 47IT to <br /> i <br /> Thus, a plot of residual drawdown s' versus the logarithm of <br /> t/t' forms a straight line. The slope of the line equals <br /> 2.30Q/4rr'T so that for Bs', the residual drawdown per log t <br /> cycle of t/t' , the transmissivity becomes 1 <br /> T 2.30Q <br /> (4.50) <br /> 47r,6 s' <br /> No comparable value of s can be determined by this recovery <br /> test method. <br /> "ql�- <br />