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<br />are shown on the left side of the figure and the sandstone layers are numbered from <br />. the top on the right side. Shale layers between the sandstone zones are marked with <br />green diagonal lines across the layer. Perforated zones in the monitoring hole are <br />located in the middle of the graph with the depths from ground surface of each <br />perforation, We see for instance that completion zone 7 corresponds to layer 9 and the <br />perforations at depths 2098, 2110, and 2130. <br /> <br />Aquifer properties were derived based on publiShed data, geophysical logs, and <br />personal communication with S. Robson, Total formation thickness is 484 ft, with a <br />total sandstone thickness of 397 ft, General aquifer parameters used in the simulations <br />are: T (transmissivity) = 2013 sqftld, S (confined storage coefficient) = 3,88E-04, Ss <br />(Specific Storage ) = l,OE-06 1ft, kv (vertical hydraulic conductivity of the confining <br />layers) = 0.016 ftId, Parameters for the individual layers are presented in Table 7.1. <br /> <br />. <br /> <br />Transmissivity of individual layers was estimated based on a derivation by Robson <br />(personal communication, 1997). For each perforated zone in the monitoring hole, we <br />can derive a k (hydraulic conductivity) value using the semi-log plot of drawdown <br />presented in the USGS report: <br /> <br />T = 2.3"Q/(4"Pi"dh) <br />S = 2.25 "rlolr" , then <br />TIS = r"/2.25"1o <br /> <br />where: <br />Q = discharge rate for this layer <br />dh = change in head per log cycle in this layer <br />r = radial distance from pumping well to observation well <br />10 = zero drawdown intercept from the semi-log plot for the zone of interest. <br /> <br />. <br /> <br />If we assume a unifonTl specific storage 55, then we have: <br />TIS = kiSs, or <br />k = Ss"T/S = Ss"r"/2,25"1o <br /> <br />21 <br />