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zl <br />~; • that corresponds to infinite :ime after the injection. Selecting arbi- <br />trarily the point on the line with coordinates -s = 3.0 feet and 1/t = <br />' 0.013 min-l, the transmissivity was calculated as: <br />T = V (0.52)(0.013) 1.7 x 10-4 ft2/min <br />4nt -s ~ 4n(3) <br />Drawdown test data were analyzed using the Jacob method. Data from <br />observation well 118 were used to illustrate the procedure. The measured <br />drawdown was plotted on the coordinate axis of semi-log paper vs time <br />on the log axis as shown in Figure 11. The straight-line. portion of the <br />plot is projected to intercept one or more log cycles and the zero draw- <br />down axis. The values of transmissivity and storage coefficient were <br />computed as follows: <br />T = 243034 = 2.3034 0.346 = 2 x 10 2 ft2lmin <br />• <br />and r <br />S , 2.246Tto = (2.246)(2x10-2)(42) = 7.6 'x 10 4 <br />r2 (50)2 <br />where: <br />es = drawdown over one log cycle, <br />'to = time at zero drawdown intercept, and <br />r =distance from pump well to observation well. <br />Data from well 117 are used to illustrate the procedure for analysis <br />of recovery data. The measured drawdown was plotted do the coordinate <br />scale of semi-logarithmic paper and the corresponding value of t/(t-tp) <br />' on the log scale as shown in Figure 12, where tp is the duration of the <br />pumping period. The slope of the line is 15.15 feet per lag cycle which <br />yields a transmissivity of: <br />.. T = 2_ 303Q = 2.303 0.146 _ 1.17 x 10-3 ft2/min <br />4uAS 4,r 15.15 <br /> <br />