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The Bear No. 1 and 2 portals have been backfilled and graded as part of the Bear No. 1 <br />and 2 reclamation. The portal at the Bear No. 2 Mine was backfilled to an elevation <br />approximately one-half the height of the highwall. This configuration achieves the static <br />safety factor of 1.3 required by Rule 4.14 by assuming an internal angle of friction (41 °) <br />of the foundation material which exceeds the laboratory value (34°). A report by Rocky <br />Mountain Geotechnical indicated that the actual internal angle of friction may exceed the <br />minimum 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 has not <br />indicated any stability problems. <br />Bear Coal Company has modified the existing unreclaimed Edwards mine portals and <br />added additional portals to access the Bear No. 3 Mine. Bear Coal Company submitted <br />a geotechnical investigation and stability analysis of the portal access road and portal <br />Facilities, prepared by Rocky Mountain Geotechnical, Inc. This report analyzed the <br />>tability of the existing slope, several proposed alternative portal construction plans, and <br />>everal reclamation configurations for this area. <br />The geotechnical investigation and stability analysis determined that the affected bedrock <br />:dope stability above the mine portals could be improved by the excavation of a thin <br />:>urficial deposit of colluvial debris. The resulting surface would be in a stable, <br />Nock-bolted sandstone face. <br />'The geotechnical investigation and stability analysis determined that the portal cut slope <br />;tnd bench fills cannot attain static slope safety factors in excess of 1.3, as required by <br />Rules 4.14 and 4.27. After reclamation, the static slope safety factor will be less than 1.3. <br />"fhe static slope factors attained by the reclaimed configurations represent decreases of less <br />Than five percent of the existing stability factors for the same areas. <br />Bear Coal Company has installed appropriate monitoring facilities in order to verify the <br />stability of the operational and reclaimed slope stability of the portal access road and <br />Mortal facilities. <br />"fhe Division considers the backfilling and grading plan for the Bear No. 3 Mine to be in <br />conformance with the permanent program regulations with the imposition of two <br />:,tipulations in the original Findings Document. Detailed engineering plans (Stipulation <br />IJo. 10), and portal bench monitoring (Stipulation No. 21) were requested by the <br />Division. Stipulation No. 10 has been satisfied. Monitoring facilities as required by <br />Stipulation No. 21 have been installed. The monitoring requirement is still in effect. <br />1Jo underground development waste was placed on the surface at the Bear No. 3 Mine. <br />"fhe Bear Coal Company disposed of underground development waste within the <br />abandoned workings (First East panel) of the No. 3 mine. <br />\~Vith the stipulation, the Bear Coal operation is in compliance with the provisions of this <br />section. <br />25 <br />