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AVCOLORADO <br />Division of Reclamation,- <br />Mining and Safety <br />Department of Natural Resources <br />1313 Sherman Street, Room 215 <br />Denver, CO 80203 <br />November 7, 2014 <br />William A. Bear <br />Bowie Resources, LLC <br />P.O. Box 483 <br />Paonia, CO 81428 <br />Re: Bowie No. 2 Mine (Permit No. C- 1996 -083) <br />Technical Revision No. 94 (TR- 94) <br />Cover Material Storage on Gob Pile #2 <br />Preliminary Adequacy Review <br />Dear Mr. Bear: <br />The Division has reviewed the application submitted by JE Stover and Associates on behalf of <br />Bowie Resources, LLC (BRL) for Technical Revision No. 94 (TR -94) for the Bowie No. 2 Mine. The <br />revision proposes to stockpile cover material on the second bench of Gob Pile #2. <br />The application included a Stability Evaluation performed by Huddleston -Berry Engineering & <br />Testing (HBET). HBET's evaluation demonstrated that with the stockpiled material in place, the <br />requisite Static Factor of Safety of 1.5 can be maintained on Gob Pile #2, assuming that pore <br />pressures (as measured by Vibrating Wire Piezometers already installed) do not rise <br />significantly. The Division does, however, have a few comments that should be addressed: <br />1. The configuration of the Proposed Coverfill Stockpile is provided graphically on Figure 1 of <br />the HBET document. Based on the contour spacing, it appears that an outslope of <br />approximately 2h:1v is being proposed. However, neither the revised permit text nor <br />HBET's report describe the proposed configuration of the coverfill. Please revise the permit <br />text to describe approximate dimensions (width and height), outslope, and volume for the <br />Proposed Coverfill Stockpile. <br />2. Please revise HBET Figure 1 to show the locations of the various VWP installations; HBET's <br />study refers to the piezometers, and depicting their locations will add clarity to the report. <br />3. The Pore Pressures subsection of HBET's evaluation (page 5) speaks to "increases" in pore <br />pressures that would be necessary in order to reduce the Factor of Safety to less than 1.5. <br />These numbers fail to inform the reader unless the reader knows the pressures in existence <br />p co, <br />1313 Sherman Street, Room 215, Denver, CO 80203 P 303.866.3567 F 303.832.8106 http: / /mining.state.co.us I <br />John W. Hickenlooper, Governor Mike King, Executive Director Virginia Brannon, Director * * IM76 <br />