Laserfiche WebLink
MINE ENGINEERING <br />MINE RECLAMATION <br />February 8, 2013 <br />J. E. STOVER & ASSOCIATES, INC. <br />2352 NORTH 7 STREEET, UNIT B <br />GRAND JUNCTION, COLORADO 81501 <br />PHONE: (970) 245 -4101, FAX 242 -7908 <br />Susan Burgmaier <br />Division of Reclamation, Mining & Safety <br />1313 Sherman St., Room 215 <br />Denver, CO 80203 <br />Re: Bowie Resources, LLC, Bowie No. 2 Mine <br />Technical Revision Application No.75, Adequacy Response #2 <br />Permit C -1996 -083 <br />Dear Ms. Burgmaier: <br />1. DRMS: Item resolved <br />2. DRMS: Item resolved <br />3. DRMS: Item resolved <br />Rule 4.10.4 Coal Mine Waste Banks- Construction Requirements <br />RECEIVED <br />FEB 1 1 2013 <br />Division of Reclamation, <br />Mining & Safety <br />CIVIL ENGINEERING <br />CONST. MANAGEMENT <br />The DRMS' letter dated December 6, 2012 requested additional information. On behalf of Bowie <br />Resources, LLC, enclosed is the requested data. <br />Rule 2. 05.3(4) - Operations Plan for Ponds, Impoundments, Other Treatment Facilities <br />and Diversions <br />4. DRMS: The Division's initial review of the as -built topography provided with the TR -75 <br />application indicated that portions of Gob Pile #4 were constructed with steeper slopes than <br />what was approved in the original design for the pile. On an attached map (attached hereon <br />for your reference), we identified areas of the slope that appeared to be between 2.0H:1 V <br />and 2.5H:1 V, and other areas that were steeper than 2.0H:1 V (blue -green areas). <br />BRL contracted Buckhorn Geotech, Inc. to further examine the stability of the refuse area. <br />Buckhorn has conducted a revised as -built stability analysis, and determined that slopes as <br />steep as 2H:1 V will provide the required minimum factor of safety of 1.5. However, in the <br />conclusions section of the memo, Buckhorn recommends "that the areas highlighted in the <br />DRMS letter of October 31, 2012 be surveyed to confirm the slopes in those areas. Any <br />areas steeper than 2H:1V should be re- graded to achieve a slope with a minimum F.S. of 1.5 <br />as required ". <br />BRL will need to ground -truth the contours of Figure 2 and identify and re -grade any <br />segments steeper than 2.0H:1 V, in order to achieve the required factor of safety. This <br />work must be completed and submitted to the Division before TR -75 can be approved, <br />and no cover material should be placed on Gob Plle #4 until TR -75 has been approved. <br />