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the results have to be questioned because of the q factor, or slug volume. in <br />• the equation. The volume of 10 feet of 2" I.D. casing is only only about <br />1.6 gallons. Since 9 gallons was "slugged" into the well on top of 0.7 gallons <br />left in the casing from the previous slug, a value of 9.7 had to be used as q. <br />It is very clear, however, that a dramatic lithologic difference above forty <br />foot level very rapidly drained most of this volume, before the first reading <br />could be taken. In fact the volume lost in the first 45 seconds before a <br />water level could be taken was equilvalent to a little over 50 feet of 2 inch <br />casing volume. Therefore, the Ferris and Knowles methodology results are <br />unreliable, but appear to corroborate the observation that material above <br />40 feet, for an unknown thickness is relatively permeable. <br />A third methodology was utilized to evaluate test results from well GWS-22, that <br />of Cooper, Bredehoeft and Papadopulos, (in Lohman, 1972). This methodology <br />is also a variation of the Theis equation, but utilizes a family of type curves <br />developed expressly for slug tests. <br />• Figure 2 is a graphical illustration of the data with Ho/H <br />Where H = head at start of test <br />0 <br />H = head at time of measurement <br />In case of a slug removal test H/Ho would be graphed, but the hydraulic <br />geometry, and; therefore, the method of analysis remains the same. <br />Curve matching shows a best fit on the oC = 10 1 Curve <br />Where: <br />T <br />t <br />rc <br />and T <br />• <br />= transmissivity <br />= time in seconds at match point <br />= radius of well or piezometer casing <br />= 0.1 rc2 <br />t <br />= 1.7 X 10 6ft2/sec = 0.14 ft2/day <br />7-9-25 <br />