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CLEARWATER <br /> G R O U P, I N C. <br /> If, it is determined that the test was performed under confined aquifer <br />' conditions and enough time has elapsed for steady-state conditions to have <br /> been met (as defined in the literature), the Jacob distance-drawdown and <br />' time-drawdown methods (Cooper & Jacob, 1946) will generally be applied to <br /> evaluate storativity and transmissivity. Alternatively, the Theis curve- <br /> fitting method (Theis, 1935) may be employed if steady-state conditions were <br /> not reached. In leaky aquifers, the Hantush method (Hantush, 1956) will <br />' generally be used. <br /> The capture zone will also be determined using the transmissivity values <br />' obtained through the evaluation and following the method initially outlined <br /> by Janvandel and Tsang (1986). The data will then be used to determine the <br />' construction and design specifications of the proposed system, based on the <br /> requirements of the system.conceptual design (migration control, dewatering, <br /> plume capture). <br />' It. must be recognized .that even_.using theoretical models for .the data <br /> evaluation, some judgement will be necessary in conducting the analyses and <br /> applying the calculated parameters to the system design. Different types of <br /> aquifers may have similar drawdown or response behaviors, and-this must be <br /> accounted for. A complete explanation of the method used and the reasoning <br />' behind the choice of method and an analysis of the results will be presented <br /> with the data evaluation. <br /> REFERENCES <br />' Boulton, N.S. (1954). The drawdown of the water table under nonsteady <br /> conditions near a pumped well in an unconfined formation. Inst. Civil <br /> Engrs., Proc.,.Vol. 3, p. 564-579. <br /> Cooper H.H. & Jacob, C.E. (1946). A generalized graphical method for <br /> evaluating formation constants and summarizing well field history. Am. <br />' Geophys. Union Trans. Vol. 27, p..526-534. <br />' Creative Scientific Applications (1992-1994). The Aquifer Test Toolbox, <br /> Aquifer Test Worksheets for Hydrogeologists and Engineers. Ver. 1.0., <br /> Wellsville, Penn. <br /> Hantush, M.S. (1956). Analysis of data from pumping tests in leaky aquifers. <br /> J. Geophys. Res. Vol. 64, p. 1043-1052. <br /> Constant-Discharge Aquifer Test Page 4 of 5 December 16,1994 <br />