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<br />Taking the values obtained <br />• <br />h2 - hl = 2.04 ft. <br />t2 - tl = 257 sec <br />D 11.9 ft. <br />R = 0,08 ft. <br />S = 6 <br />K = 5 X 10 -7 ft/sec <br />= 1.3 cm/day <br />This is clearly a low permeability value. It is a value typical of a silty <br />or loamy clay or very fine silty sand. <br />Another methodology was used as a check on the first value. The method used <br />is a slug test method developed by Ferris and Knowles ( in Bentall et al „ 1963) <br />This methodology is based upon the Theis equation and utilizes a graphical <br />technique. Figure one illustrates the graphical results of the test; this <br />figure illustrates the effect of actual change in storage over time (hence <br />a curved instead of a straight line). Two seperate points (shown on Figure 1) <br />were used to calculate transmissivity according to the equation <br />T = 114,6 q (1/tm) <br />s <br />where s =residual head (feet) <br />an~i tm =time since test began (minutes) <br />LJ <br />Analysis by this method results in a (geometric mean) value of T=55.4 ftZ/day. <br />Dividing this transmissivity value by a saturated thickness of 11.9 feet <br />(initial head). a hydraulic conductivity of 4.65 ft/day is calcule.ted. However, <br />7-9-23 <br />