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<br />Problems concerned with values of ~a2~ other than those for <br /> <br />which curves are shown in Figures 2 and 3 generally can be solved with <br /> <br />an acceptable degree of accuracy by interpolation, but if the user <br /> <br />desires a more accurate appraisal, separate computations can be made. <br /> <br />Because computations of residual effects sometimes involve small <br /> <br />differences between large numbers, use of tabular values may be <br /> <br />preferable. The computations shown in Table 2, which are the basis <br /> <br />for the curves labeled ~iI/st~ = 0.35 in Figures 2 and 3 and the curve <br /> <br />in Figure 4, will serve as an illustration of how additional curves <br /> <br />can be constructed. <br /> <br />The curve labeled q in Figure 4 shows the relation between q and <br /> <br />" <br /> <br />~ resulting from pumping a well 3,656 feet from a stream at a rate of <br /> <br />I. <br /> <br />10 acre-ft/day for 35 days. The ratio of !/~ is 13.37 X 1<1' ft2/day, <br /> <br />which is not an unusual value for an alluvial aquifer. The sdf is <br /> <br />100 days. The pumping rate is 10 acre-ft/day; the maximum rate of <br /> <br />stream depletion is 2.7 acre-ft/day. Pumping ceases at the end of <br /> <br />35 days; the maximum rate of stream depletion occurs about 10 days <br /> <br />later, and q still is about half the maximum rate 45 days after <br /> <br />cessation of pumping. <br /> <br />. <br /> <br />~' <br />~ <br />~. <br />~ <br /> <br />13 <br />