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- 18 - -� <br /> . TABLE 2 <br /> CALCULATED SUBSIDENCE RATIOS <br /> POINT TOTAL A-B BED M BED TOTAL COAL SUBSIDENCE <br /> NO. SUBSIDENCE REMOVED REMOVED REMOVED RATIO <br /> TP-1 -1.94 9.00 0 9.00 0.22 <br /> TP-2 - 0 0 0 <br /> TP-3 - 0 0 0 - <br /> TP-4 -0.19 8.00 0 8.00 0.02 <br /> TP-5 -0.91 7.00 8.00 15.00 0.06 <br /> TP-6 -0.89 10.00 0 10.00 0.09 <br /> MC-1 +0.01 8.00 0 0 0.00 <br /> MC-2 -2.03 8.00 0 8.00 0.25 <br /> MC-3 -0.90 8.00 0 8.00 0.11 <br /> MC-4 -2.10 8.00 8.00 16.00 0.13 <br /> MC-5 -1.73 8.00 0 8.00 0.22 <br /> MC-6 -0.48 8.00 0 8.00 0.06 <br /> MC-7 +0.01 10.00 0 10.00 0.00 <br /> MC-8 +0.04 0 0 0 - <br /> MC-9 +0.02 0 0 0 - <br /> MC-10 -0.32 10.00 0 0 0.03 <br /> MC-11 -0.47 10.00 0 0 0.05 <br /> MC-12 -0.10 10.00 0 0 0.01 <br /> MC-13 -0.17 10.00 0 0 0.02 <br /> • MC-14 _ 0 0 0 _ <br /> MC-15 0 0 0 <br /> MC-16 - 0 0 0 <br /> As was previously discussed, two sets of points were used to <br /> approximate the actual angle of draw in the Coal Basin area. <br /> These were MC-13 and MC-14 in conjunction with -longwall face <br /> 102 , Dutch Creek No. 1 mine, and TP-201 TP-4 and MC-8 , marginal <br /> to long-wall face 301 , L.S . Wood No. 3 mine. In the first case, <br /> the data points are closely spaced; MC-13 and MC-14 are 178 <br /> feet apart, and in turn MC-13 was 743 feet ahead of longwall <br /> 102 on the date of the last survey, 8/9/85 . This data spacing <br /> allows calculation of angle of draw to within +/-1 .67 . <br /> Assuming that subsidence is present halfway between pints <br /> MC-13 and MC-14 , an approximate actual angle of 16 .48 was <br /> determined. A diagrammatic representation of the relationship <br /> between the mine workings and these points, along with the <br /> detailed calculations, are given in Figure 20, next page. <br /> It is clear, however, that the 0angle of draw in this area would <br /> actually be greater than 16 .48 after stabilization. It cannot <br /> be assumed that MC-13 , the last point in the MC-10.-16 series <br /> that had moved as of 8/9/85 , is stable, or that', even if the <br /> face stopped on the date of the survey, point MC-14 would not <br /> subsequently subside with time. In addition, the advance of <br /> face 102, about 4 .5 feet per day in early August, certainly <br /> has an effect on what amounts to a moving angle of draw. <br /> l <br />