Laserfiche WebLink
• <br />ENVIROCON, INC. <br />395 WEST IRONWOOD DRIVE <br />SOUTH SALT LAKE CITY. UTAH 84115 <br />TELEPHONE: X801) a86-9565 <br />FAX: (601) a85-iaaa <br />EN»IROCON, INC. <br />January 11, 1995 <br />Mrs. Kathy Welt <br />Mountain Coal Company <br />West Elk Mine <br />P. 0. Box 591 <br />Somerset Co 81434 <br />ENV # 1430.30040 <br />RE: LONE PINE DEVELOPMENT WASTE PILE DESIGN <br />Dear Kathy: <br />• The following letter summarizes the modification to the design of the Lone Pine <br />development waste pile, as approved in a previous technical revision. The design <br />follows the guidelines set forth in the Regulations of the Colorado Mined Land <br />Reclamation Board for Coal Mining. <br />Topsoil stripping: <br />As addressed in a previous, approved revision the area for the development <br />waste pile will be stripped of topsoil approximately 1 foot deep and will be placed in <br />the Lone Pine topsoil pile previously submitted under separate cover. <br />Stability Analysis: <br />• <br />The development waste pile was designed to have a factor of safety greater <br />than 1.50. The development waste pile is approximately 0.70 acres. The pile was <br />designed to store 17,000 cubic yards. The following paragraphs describe the slope <br />stability analysis. <br />A slope stability analysis was perfonned on a profiled depicted on drawing LPG <br />-103F. The slope stability analysis utilized the PCSTABL5 program to determine the <br />factors of safety against failure. The factor of safety is the ratio of the forces resisting <br />the slope movement to the forces which cause the slope to fail. The resisting forces <br />are determined by the shear strength of the native soils to resist failure along a <br />specific surface. <br />A~y~Compeny <br />~L~S <br />~0 <br />