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<br />A. J. Waldron -2- October 16, 1995 <br />Annual Subsidence Report <br />1. The Division notes the subsidence monitoring plan <br />contained in the permit may not meet the requirements of <br />Rule 2.05.6(6)(c). The Division approved the current <br />subsidence control plan by its approval of technical <br />revision No. 016 on February 11, 1992. By letters to the <br />Division dated July 14, 1994 and August 3, 1994, the <br />prior Operator explained in great detail why the existing <br />subsidence monitoring program satisfies the Rules. Prior <br />to responding to the Division's concerns, Bowie requests <br />that the Division review the two letters. <br />2. The Division notes that the prior Operator had difficulty <br />surveying with a reliable degree of accuracy. Bowie <br />recognized this problem and has retained UTE Engineering <br />& Surveying Company to perform the survey portion of the <br />required subsidence monitoring. <br />The Division notes that stations 94, 96, 97 and 98 all <br />show different data for the same date compared to the <br />data reported in 1993. These survey stations are the <br />Grosse-Rhodes structures. When Bowie was preparing the <br />annual subsidence report it reviewed the survey notes and <br />calculations prepared by the prior Operator for these <br />stations. The prior Operator had a error in its <br />calculations for the elevation of stations 94, 96, 97 and <br />98 for the survey performed on 12-08-93. <br />Mine Inflow Report <br />No response required. <br />Please call if you have any questions. <br />Sincerely, <br />Jim Stover, P.E. <br />Consulting Engineer <br />cc: Basil Bear <br />