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disposal requirements The water will be removed to an appropriate dis osal facility by a licensed
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<br /> Itransporter
<br /> Data Evaluation
<br /> Data collected dunng the aquifer test will be evaluated using various graphical and numerical methods,
<br />' depending on flow (steady or unsteady state) well construction (fully or partially penetrating) and aquifer
<br /> type (confined, leaky, unconfined, or semi-confined) The aquifer test will be evaluated using more than one
<br /> method Analysts of the aquifer test data will be conducted utilizing computer software
<br />' A majority of the aquifer will be conducted using partially penetrating wells in unconfined aquifers under
<br /> steady state conditions In general, the curve-fitting method presented by Neuman (1975) or by Boulton
<br />' (1954) will be used to evaluate transmissivity, storativity and vertical hydraulic conductivity under these
<br /> conditions (the Boulton method assumes nonsteady state conditions) The Stretitsova's curve-fitting method
<br /> presented by Kruseman and de Ridder (1990) may also be used for unconfined conditions In addition, the
<br /> steady state well equation may be applied (Todd, 1980) to evaluate the hydraulic conductivity (away from
<br /> the pumping well)
<br /> If it is determined that the test was performed under confined aquifer conditions and enough time has
<br />' elapsed for steady-state conditions to have been met (as defined in the literature), the Jacob distance-draw
<br /> down and time-draw down methods (Cooper & Jacob, 1946) will generally be applied to evaluate storatzvrty
<br /> and transmissivrty Alternatively, the Theis curve-fitting method (Theis, 1935) may be employed if steady-
<br /> state conditions were not reached In suspected leaky aquifers, the Hantush method (Hantush, 1956) will
<br /> generally be used
<br /> The capture zone will also be determined using the transmsssivity values obtained through the evaluation
<br /> and following the method initially outlined by Janvandel and Tsang (1986) The data will then be used to
<br /> determine the construction and design specifications of the proposed system, based on the requirements of
<br /> the system conceptual design(migration control, dewatering, plume capture)
<br />' It must be recognized that even using theoretical models for the data evaluation, some judgment will be
<br /> necessary in conducting the analyses and applying the calculated parameters to the system design Different
<br /> types of aquifers may have similar draw down or response behaviors, and this must be accounted for A
<br />' complete explanation of the method used and the reasoning behind the choice of method and an analysis of
<br /> the results will be presented with the data evaluation
<br />' References
<br /> Boulton, N S (1954) The draw down of the water table under nonsteady conditions near a pumped well in
<br /> an unconfined formation Inst Civil Engrs, Proc , Vol 3, p 564-579
<br />' Cooper, H H & Jacob, C E (1946) A generalized graphical method for evaluating formation constants and
<br /> summarizing well field history Am Geophys Union Trans Vol 27, p 526-534
<br />' Creative Scientific Applications (1992-1994) The Aquifer Test Toolbox, Aquifer Test Workshects for
<br /> Hydrogeologists and Engineers Ver 1 0 , Welisville, Penn
<br />' Hantush, M S (1956) Analysis of data from pumping tests in leaky aquifers J Geophys Res Vol 64, p
<br /> 1043-1052
<br /> Javandel, 1 & Tsang, C , (1986) Capture-zone-type curves a tool for aquifer cleanup Ground Water, Vol
<br /> 24,No 5,p 616-625
<br /> Kruseman, G P , & de Ridder,N A (1991) Analysis and Evaluation of Pumping Test Data, 2nd edition,
<br />' International Institute for Land Reclamation and Improvement, Wageningen, The Netherlands
<br /> Neuman, S P (1975) Analysis of pumping test data from amsotropic unconfined aquifers considering
<br /> delayed gravity response Water Resources Res , Vol 10,p 303-312
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