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<br />DESCRIPrION OF CURVES AND TABLES <br /> <br />Effects during Pumping <br /> <br />Curves ~ and ~ in Figure 1 apply during the period of steady <br /> <br />pumping. Curve ~ shows the relation between the dimensionless term <br /> <br />tT/l.[ and the rate of stream depletion, s., at time !.' expressed <br /> <br />as a ratio to the pumping rate~. Curve ~ shows the relation between <br /> <br />!J;J{!2.[ and the volume of stream depletion, .l:::, during time 1., expressed <br /> <br />as a ratio to the volume pumped,~. The coordinates of both curves <br /> <br />are tabulated in Table 1. The number of significant figures shown for <br /> <br />the values tabulated in Table 1 was determined by needs for some of the <br /> <br />computations described in the next section, which sometimes involve <br /> <br />small differences between relatively large numbers. Precision to more <br /> <br />. <br /> <br />than 2 significant figures in reporting results probably will never be <br /> <br />warranted. <br /> <br />Residual Effects <br /> <br />If there is no capture of water from other sources, the stream <br /> <br />will continue to lose water after pumping stops. As time approaches <br /> <br />infinity, the volume of stream depletion approaches the volume pumped. <br /> <br />The rate and volume of depletion at any time after cessation of pumping <br />, <br /> <br />can be computed using the method of superposition, that is, by assuming <br /> <br />, . <br /> <br />that the pumping well continues to pump, and that an imaginary well at <br /> <br />'. <br /> <br />the same location is recharged continuously at the same rate the <br /> <br />pumping well is discharging. Residual effects are shown in Figures 2 <br /> <br />and 3 for five selected values of ~/sr.[. <br /> <br />The ~i is the time after <br /> <br />cessation of pumping. <br /> <br />109'1 <br /> <br />8 <br />