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<br />J. E. STOVER & ASSOCIATES, INC. <br />2352 NORTH 7`h STREET, UNIT B <br />GRAND JUNCTION, COLORADO 81501 <br />PHONE: (970) 245-4101, FAX 242-7908 <br />MINE ENGINEERING <br />MINE RECLAMATION <br />October 13, 2009 <br />J.1. Dudash <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 />TR-65 - B-Seam Room & Pillar Mine Plan <br />Permit C-1996-083 <br />Dear Mr. Dudash: <br />CIVIL ENGINEERING <br />CONST. MANAGEMENT <br /> <br />On behalf of Bowie Resources LLC, enclosed is an application for Technical Revision to amend <br />the B-Seam mine plan. BRL plans to perform some room and pillar mining southeast of mined <br />out Panels B-2 and B-3. This mining will be performed near the outcrop so rockfall hazard and <br />outcrop barrier pillar failure are a concern. The following discussion should address these <br />concerns: <br />Subsidence Section of the Permit <br />Recognition of Rockfall Hazard <br />1. Page 2.05-99 states "However, structures below the coal seam to be mined may be <br />damaged by landslides or rockfalls activated by subsidence." <br />Aerial extent of Rockfall Rollout <br />2. Page 2.05-106 states: "The aerial extent of predicted subsidence related phenomena <br />within the permit and adjacent area is shown on Map 27 Subsidence. Traditional <br />subsidence and predicted rock roll out areas are both shown on Map 27. The aerial <br />extent for the traditional subsidence is calculated based on a 25 degree angle of <br />draw over areas where subsidence is expected to occur. The rock roll out areas are <br />predicted using the Colorado Rockfall Simulation Program, version 4.0, developed by <br />the Colorado Department of Transportation, the Colorado School of Mines and the <br />Colorado Geological Survey. The results of the rock roll out predictions are <br />presented in Volume VII, Geotechnical Studies, Tab 11."