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<br />Each of the two wells tested represented different situations which <br />demanded a different approach. The first well, GWS-22, was completed <br />predominantly in highly anisotropic, dragline spoils. The well <br />contained about two feet of water which probably represented perched <br />water, or water held in the sump created in the shale by the drill <br />hole. This situation, particularly when using a reverse slug test, <br />represents a case where a saturated hydraulic conductivity test is <br />being run in originally unsaturated materials. This situation is <br />acceptable provided that the test is allowed to equilibrate over time. <br />Due to changing gradients, trapped air and actual physical changes, <br />due to wetting, of the material being tested. the measured permeability <br />will decrease over time until (graphically) the values assymptotically <br />approach some value. At this point the hydraulic. conductivity should <br />be calculated (Bouwer, 1978, Noyes and Stoner, 1979). Measurement of <br />hydraulic conductivity prior to obtaining stabilized (nandecreasing) <br />• values means that the soil-water system is somewhere on a hysteresis <br />loop so that the value obtained is not unique. <br />Many slug test procedures are designed to be used in wells or piezometers <br />tapping confined aquifers. Use of such test procedures, generally involving <br />the Theis equation, was not derived to obtain transmissivity and storage <br />coefficient values for water table conditions. However. in the experience <br />of WATEC,INC. the results of testing and analyses for permeability and <br />porosity using the Theis equation compares favorably with results obtained <br />by more rigorously correct methods. <br />Results and Conclusions <br />Well GWS-22 <br />As mentioned previously Well GWS-22 is completed in replaced dragline spoil, <br />• <br />7-9-27 <br />