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Tne Mining and Reclamation Flan for Somerset Mine contains a request fer a variance to restoring three areas to appro:~imate original contours. refer to pages ~.Oc-4 to ~.06-1U. Steep slopes ma{::e restoration of the Eear and Hubbard Car,yor, ventila*_ion facilities and the bear Canyon B Seam degas site impra~=tical. U. S. Steel Mining Co. conducted a stability analysis of the proposed final contours contained in the Somerset Mine permit application. GENERAL The Rotational Equilibriu,n :,nalysis of Multilayered EmbanV:ment (REAME) program, developed by the University of F.:entucky, was _.s~d ~_ per-;r_~rm the safety foes or calculations. A circular failure surface 1s assumed under a rotating mass. The mass is divided into slices ar,d the sum of moments tending to cause and resist failure are determined. The safety factor is the ratio of theses two sums. REAME can calculate the safety fatter using either tha normal method or the simplified bishop method. .;il ~-alculati~=~r~s were completed using the simplified bishop rr,ethad. Soil samples were analy=ed to determine the internal angle of frictior, and cohesion. One sample wa.s tat::en along th,e cross section Iine C-C shown on Map CB-12'1 in Hubbard Cree6:. This sample was used to model the soil characteristics of the uncon- solidated alluvial material in Hubbard CreeV;. A second soil sample was taken at the Eear Creek Fan. This sample was used to model the soil characteristics of the bear Canyon Fan Area and the B-Sean, Pegas Hole (both are located in bear Cree(::). During the summer of 158=. J.F.T. Agapito ar,d Associates conducted rc•ck mechani•=s studies underground in Hubbard Creek area of Somerset Mine. These studies de±ermined *_he.± average properties fer the roof roc4: are as follows: Unconfined Compressive Strength 1~~r14 psi Cohesior~ =•.4^ psi (54,438psf) Angle of Internal Friction 4U.1~ degrees These values were used to represent the properties of any rock outcrops er~countered in the analysis. B SEAM DEGAS HOLE AREA - BEAR CREE1::: ----------------------------------- Map A8-1;89 contained in the Somerset Mine Mining and Reclamation Flan (page 2.~J6-8) shows a plan view and cross section of the degas hale area. U. S. Steel Mining Co. investigated the area along section A-A and determined the geologic structure shown on Exhibit A. This was then used to develope the section shown in E>:hibit b on which the stability analysis was conducted.