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<br />Proposed Decision <br />The Colorado Division of Minerals and Geology proposes to approve, <br />with one stipulation, Technical Revision-023 to the Mining and <br />Reclamation Permit for the Somerset/ Sanborn Creek Mine, Permit No. <br />C-81-022. The revision involves clarification of the variance from <br />approximate original contour and modifying the reclamation plan for <br />backfilling and grading at the Bear Canyon portal facilities. The <br />modification involves a significant change to the post-mining <br />contours from what was previously approved by utilizing more of the <br />historic portal development waste and road fill beneath the portals <br />to blend the portal slope face-up into the existing adjacent <br />topography. Details of these changes are included in the findings <br />of compliance and the revision file. <br />Findings of Compliance <br />Technical Revision-023 was submitted to modify the reclamation plan <br />at the Bear Canyon facilities, specifically, the backfilling and <br />grading portion of the approved plan. This portion of the plan <br />came into question during an inspection as to whether a proper <br />variance from approximate original contour (AOC) had been granted <br />for the backfilling since the approved plan would not meet AOC. <br />Upon reviewing the permit, it was determined that the variance had <br />been inappropriately granted and the operator was required to <br />submit a revision to the permit to satisfy all of the requirements <br />for the AOC variance. <br />Rule 2.06.5(2) outlines the requirements for receiving a variance <br />from approximate original contour in steep slope mining areas. The <br />operator has now complied with all seven requirements of this AOC <br />variance with the exception of 2.06.5(2)(f) requiring that the <br />backfill meet a static factor of safety of at least 1.3. This is <br />explained in more detail below. In addition, the operator has <br />modified the reclamation plan such that any variance from AOC is <br />now negligible, however, since the variance has been properly <br />demonstrated, the operator will retain it. <br />In modifying the reclamation plan to utilize more spoil material <br />and better blend with the existing topography, the operator was <br />unable to meet the static factor of safety of 1.3 for all <br />backfilled areas. The predicted static factor of safety ranges <br />from 1.09 to 1.25. Based on a technical review by Division <br />personnel, it was determined that the technical assumptions and <br />methodology used in completing the analysis were correct and it was <br />concluded that this proposed plan will improve the existing site <br />