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• configuration achieves the static safety factor of 1 .3 required by Rule 4.14 by <br />assuming an internal angle of friction (4101 of the foundation material which <br />exceeds the laboratory value (340). A report by Rocky Mountain Geotechnical <br />indicated that the actual internal angle of friction may exceed the minimum <br />value obtained in the laboratory due to the high density of the foundation <br />material present at the site. Stability monitoring of the Bear No. 2 portal area <br />has not indicated any stability problems. <br />Bear Coal Company has modified the existing unreclaimed Edwards mine portals <br />and added additional portals to access the Bear No. 3 Mine. Bear Coal <br />Company submitted a geotechnical investigation and stability analysis of the <br />portal access road and portal facilities, prepared by Rocky Mountain <br />Geotechnical, Inc. This report analyzed the stability of the existing slope, <br />several proposed alternative portal construction plans, and several reclamation <br />configurations for this area. <br />The geotechnical investigation and stability analysis determined that the <br />affected bedrock slope stability above the mine portals could be improved by <br />the excavation of a thin surficial deposit of colluvial debris. The resulting <br />surface would be in a stable, rock-bolted sandstone face. <br />The geotechnical investigation and stability analysis determined that the portal <br />• cut slope and bench fills cannot attain static slope safety factors in excess of <br />1.3, as required by Rules 4.14 and 4.27. After reclamation, the static slope <br />safety factor will be less than 1.3. The static slope factors attained by the <br />reclaimed configurations represent decreases of less than five percent of the <br />existing stability factors for the same areas. <br />Bear Coal Company has installed appropriate monitoring facilities in order to <br />verify the stability of the operational and reclaimed slope stability of the portal <br />access road and portal facilities. <br />The Division considers the backfilling and grading plan for the Bear No. 3 Mine <br />to be in conformance with the permanent program regulations with the <br />imposition of two stipulations in the original Findings Document. Detailed <br />engineering plans (Stipulation No. 101, and portal bench monitoring (Stipulation <br />No. 21) were requested by the Division. Stipulation No. 10 has been satisfied. <br />Monitoring facilities as required by Stipulation No. 21 have been installed. The <br />monitoring requirement is still in effect. <br />No underground development waste is placed on the surface at the Bear No. 3 <br />Mine. The Bear Coal Company disposes of underground development waste <br />within the abandoned workings (First East panel) of the No. 3 mine. <br />No surface placement of underground waste material is to take place at the No. <br />3 Mine. The Division finds this proposal to be in compliance with the <br />• requirements of the permanent program regulations. <br />23 <br />