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STATE OF COLORADO <br />DIVISION OF MINERALS AND GEOLOGY <br />Department of Natural Resources <br />137 3 Sherman St., Room 215 <br />Denver, Colorado 80203 <br />Phone: (303) 866-3567 <br />FAX: (303) 832$106 <br />January 28, 2004 <br />Basin Resources, Inc. <br />C/o Ron G. Thompson <br />Peak Project Management <br />3800 County Road 63.9 <br />Tririidad, CO 81082 <br />Re: Technical Revision No. 55 -Golden Eagle Mine - C-81-013 <br />Dear Mr. Thompson: <br />COLORADO <br />DIVISION O F <br />MINERALS <br />GEOLOGY <br />REC LAMATION•MINING <br />EAf ETY•SCIENCE <br />Bill Owens <br />Governor <br />Greg E. Walther <br />Executive Director <br />Ronald W. Cattany <br />Division Director <br />Natural Resource Trustee <br />We have received and reviewed the above-referenced technical revision application <br />regarding the final reclamation and closure plan for the Northwest Airshaft at the Golden <br />Eagle Mine. The plan is generally acceptable, but the following details require additional <br />clarification. Please provide a response as soon as possible so that we may proceed with <br />final approval. <br />Successful closure of the Northwest Airshaft will be dependent (in part) upon <br />allowing time for both the bentonite seal and cement grout to set-up. The plan <br />calls for allowing the bentonite seal to set-up over night and checking its level <br />with a wireline. Please verify that the operator will also follow this procedure for <br />the cement grout seal. <br />2. Please verify that the grout will be tremmied into place in successive lifts. After <br />allowing the grout to set-up overnight, additional grout placement will likely be <br />required. Please also verify that such additional grout will be added if necessary. <br />3. Provide a revised plan to include the required surface plug in accordance with <br />4.07.3(1), as cross-referenced in 4.07.3(2). <br />4. Please submit a final abandonment report following shaft closure in accordance <br />with Rule 4.07.3, and that includes a) the calculated volume of the void space to <br />be grouted following placement of the bentonite seal; b) the actual volume of the <br />grout used; c) the depth and interval of the bentonite seal and the final depth of <br />the top of the cement pug; and d) the properties of the cement grout to be used <br />including types of additives and viscosity of the mix. <br />Office of Office of Colorado <br />Mined Land Reclamation Active and Inactive Mines Geological Survey <br />