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<br />David Berry <br />-2s- <br />June 20, 1996 <br />Panel #36. Again the DMG has neglected the fact <br />that the panel will not be longwall mined and has <br />failed to considered partial extraction <br />modifications to the SEH. Figure 4 is both, <br />incorrectly used, and in no-way applicable to this <br />analysis. The example illustrated in Exhibit 15 <br />using a widely accepted practice for this analysis <br />would predict the maximum amount of subsidence for <br />this point to be 2.9'. This point is just inside <br />the zone of intermediate subsidence impact with an <br />overburden depth of 550' and the 2.9' is in the <br />range of subsidence magnitude predicted. <br />The subsidence prediction in Exhibit 15 and the <br />appropriate maps do not need to be revised because <br />BRL's subsidence predictions are correct. The <br />validity of BRL's subsidence predictions were <br />verified by Dr. John F. Abel, Jr. <br />Paragraph 5: No comment necessary. See 2.05.6(f)(v)(B) <br />Monitoring. <br />1.5 BREAK ANGLES <br />Paragraph 1: The DMG's comment regarding the general description <br />of break angles is noted. Enclosed is revised page <br />12 of Exhibit 15. <br />Paragraph 2: No comment necessary. See 2.05.6(f)(v)(B) <br />Monitoring. <br />1.6 ZONES OF POTENTIAL FRACTURING <br />Paragraph 1: See new section 1.8 in Exhibit 15. <br />Paragraph 2: The DMG reiterates its comments about unusually <br />large surface cracking observed above the 1st West <br />and 2nd West panels of the Bowie #1 mine. <br />BRL agrees that the subsidence <br />Bowie No. 1 Mine's 1st West and <br />a good lesson on how not to <br />opening adjacent to the outcrop <br />BRL suggests there is little <br />these two panels and the near <br />the Bowie No. 2 Mine. <br />effects relating to <br />2nd West panels are <br />design a wide mine <br />~. As stated above, <br />correlation between <br />outcrop portions of <br />