Laserfiche WebLink
Rule 4.23.1 Scope This Section establishes environmental protection performance standards in <br />addition to those applicable performance standards in Rule 4, to prevent any unnecessary loss of <br />coal reserves and to prevent adverse environmental effects from auger mining incident to surface <br />mining activities. <br />The Division finds that there is no unnecessary loss of coal reserves. The proposed highwall <br />mining recovers coal reserves otherwise uneconomical to extract. No adverse environmental <br />effects of highwall mining incident to surface mining activities were identified. <br />Rule 4.23.2 Performance Standards. <br />Rule 4.23.2(1) Any auger mining associated with surface mining activities shall be conducted to <br />maximize recoverability of mineral reserves remaining after the mining activities are completed. <br />Each person who conducts auger mining operations shall leave areas of undisturbed coal to <br />provide access for removal of those reserves by future underground mining activities, unless the <br />Division determines that the coal reserves have been depleted or are limited in thickness or <br />extent to the point that it will not be practicable to recover the remaining coal reserves. The <br />Division shall make such determination only upon presentation of appropriate technical <br />evidence by the operator. <br />The Division determined, upon presentation of appropriate technical evidence by the Colowyo <br />Coal Company, L.P. (Colowyo), that the remaining coal reserves are limited in thickness and <br />extent to the point that it would not be practicable to recover the remaining coal reserves. The <br />economic limits of extraction of coal by open-pit surface mining were defined and reached under <br />previously-approved permitted operations. lncreases in depths of overburden were the primary <br />reason for the economic limit ofopen-pit operations, but thickness of coal seams, partings, <br />oxidized azeas, limited aerial extent, and geologic conditions contributed to the definition of <br />economic limits as well. Conditions other than overburden were the basis for a conclusion that <br />underground mining of remaining reserves was impractical. The coal resources beyond the open- <br />pit limits were not classified as reserves by Colowyo until the concept of highwall mining <br />beyond the limits ofopen-pits was conceived. As coal resources beyond the reaches of the <br />highwall mining are limited in thickness or extent to the point that it will not be practicable to <br />recover the remaining coal reserves, the Division determines that there is no requirement to leave <br />azeas of undisturbed coal for future access. In support of this finding is that the faces of such <br />blocks of coal would be buried under backfill of the open-pits as part of the approved <br />reclamation plan, and access to the faces would be difficult. The applicant proposes not to leave <br />areas of undisturbed coal, but to extract this coal consistent with ground control of the highwall <br />operation. The Division finds this proposal in compliance with Rule 4.23.1 in that the proposed <br />action prevents any unnecessary loss of coal reserves. <br />Rule 4.23.2(2) No auger hole shall be made closer than S00 feet in horizontal distance to any <br />abandoned or active underground mine workings, except as approved in accordance with 4.19. <br />3 <br />