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most accurate. Transmissi~•ity from the straight line method (rave-776 gpd/ft) <br />lends support to the T=2283 gpd/ft from the Cooper et. al. method as the values <br />only differ by a factor of 2.9. <br />::.• <br />Assuming that the well is cemented through the alluvium as indicated by <br />the well completion report, the aquifer transmissivity is derived totally from <br />sandstones and shales of the Barren hfember. Probably most of the transmissivity <br />comes from the upper part of the well with perforations in sandstones which are <br />not compressed by a large thickness of overburden, thus permeability is increas- <br />ed by open fractures and possibly by weathering. The well has perforated sec- <br />tions in sandstone as deep as 475 feet, but these units are probably only minor <br />contributors to the total transmissivity as indicated by other wells completed <br />only in the deeper units showing low transmissivities. <br />Since the data do not give a good fit to the type curve and the aquifer <br />tested appears to be unconfined, the test data and results should be used with <br />caution. <br />Previous testing of this well by pumping 4 gpm from the well for 2 hours <br />• and measuring drawdown and recovery was performed on August 27, 1.974. In order <br />to evaluate the results of slug testing on this well, we have included an inter- <br />pretation of this previous test. A plot of recovery data for well SOM 22-H-1 <br />- (98/27/74) is included in Figure IV-12. This data shows an abrupt boundary effect <br />at s'=6.2 ft. Data plotted prior to encountering the boundary (t/t' > 10) in- <br />::. dicate T=20.7 gpd/ft., while late test data give T=459 gpd/ft. This supports the <br />idea that the high transmissivity from the slug test reflects only the upper por- <br />e tion of the well. The abrupt nature of the boundary in the pump test recovery <br />data suggest a contact between bedrock and alluvium or even the presence of a <br />single open fracture in the bedrock. In either case the high transmissivities <br />estimated from slug tests and late pump test recovery represent a small portion <br />of the strata perforated by the well. The lower transmissivity (T=20.7 gpd/£t) <br />reflects conditions in the lower bedrock portion of the well, but because of fal- <br />ling water entering the well from above during the test, this is probably an up- <br />per limit to the bedrock transmissivity. <br />:- • <br />z9 ESA Geotechnical Consultants <br />