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<br />2t ' <br />• ! immediately above and below the coal seam. The lithology of the strata <br />exposed in the open holes is described on the data sheets in Tables B1 and <br />82 in Appendix B. The geophysical logs of these intervals are in the map <br />pocket. The transmissivities determined in the tests represent weighted <br />mean values for the open intervals. Strata immediately above and below <br />the coal seam were purposely included in the test interval so that we could <br />assess the potential mine inflows from adjacent roof and floor rocks should <br />fracturing of these strata occur during mining. <br />Well LA 264 was designed to provide an assessment of the water bearing <br />capacity of the overburden in addition to that provided by the core per- <br />meability tests. The completion details for this welt are included on the <br />test data sheet in Appendix B, Table 63, and the geophysical log is in the <br />map pocket. Note that the open interval in LA 264 extends from a depth of <br />62 ft. to 276 ft. During drilling, water inflow was encountered at about <br />72 ft. and estimated to be about 15 gpm. No significant increase in dis- <br />charge was observed over the remainder of the hole. Examination of drill <br />cuttings and the geophysical to <br />• 12 ft. was produced from a thin layer of siltstone. The gamma-gamma log <br />indicates a washout (hole enlargement) beginning at 72 ft. and extending <br />to perhaps 74 ft. It is probable that a thin fractured zone at this level <br />accounts for essentially all of produced water. The "aquifer" test con- <br />ducted at LA 264 consisted of pumping at a constant rate for more than two <br />hours and the analysis of the drawdown data was accomplished using the <br />standard Jacob Method (Mc'dhorter and Sunada, 1971) as shown in Figure 5. <br />The hydraulic properties determined from these tests are summarized <br />in Table 2. Even the largest of the transmissivities in Table 2 is small <br />relative to values required for most water supply purposes. The average <br />permeabilities K are very small and are indicative of very poor water pro- <br />! during capabilities. The values of K shown in the right-hand column were <br />obtained by dividing the measured transmissivities by the thickness of. the <br />stratum believed to be contributing the water during the tests. In the <br />case of wells LA 221A and LA 218A, this stratum is the coal seam and the <br />permeability values are those for the coal. The coal permeabilities given <br />. in Table 2 fall within the range of coal permeabillties that we have measured <br />at other locations. The permeability value of 45.4 ft/d is believed to <br />