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benches which exist within the surface facilities at the Bowie No. 1 Mine. The purpose <br />of these devices is to collect additional geotechnical data with which to verify past <br />analytical assumptions and with which to complete final analysis and design, originally <br />stipulated as Phase III of the surface facility studies, within the approved original permit. <br />Utilizing the results of Geo-Hydro, Consultants, Inc.'s analyses, Merrick & Company, <br />Inc., design consultant to the operator, completed a Phase II amended design for the <br />drainage facilities at the existing surface facility azea of the Orchazd Valley (Bowie No. <br />1) Mine. The operator also completed a detailed stability analysis and redesign of the <br />proposed final reclaimed configuration for the surface facilities at the mine. This design <br />was submitted and approved in Technical Revision No. 28. The cut and fill azeas will be <br />restored [o their approximate original contour except for an access road which will <br />remain following reclamation. The access road will be within a 20 foot wide terrace <br />corridor associated with the access road. <br />In August 1986, the operator submitted a permit revision application to construct a west <br />portal facility in the East Roatcap Creek valley at the Orchazd Valley (Bowie No. 1) <br />Mine. This application proposed the construction of a new portal facility and haul road, <br />because the existing portals at the Orchazd Valley (Bowie No. 1) Mine had been <br />rendered unuseable by an underground coal mine fire. The applicant proposed to <br />upgrade an existing public access road to serve as a coal haul road to the proposed west <br />portal bench, which will be constructed by a balanced cut-and-fill method. The portal <br />bench fill includes a 130-foot maximum height terraced earthen fill constructed across <br />East Roatcap Creek. Maximum interterrace facial slopes shall not exceed a 2.Sh:1.Ov <br />(horizontal to vertical) slope gradient. A 48-inch concrete culvert was installed beneath <br />the cross valley fill to accommodate the 100-year flow of the East Roatcap Creek. <br />The permit revision application included geotechnical specifications documented in the <br />Orchard Valley (Bowie No. 1) West Mine Appendix, Volume 6, prepazed by Golder and <br />Associates, consultants to the operator. This appendix presents the results of <br />geotechnical investigations, stability analyses and detailed engineering designs for the <br />west portal bench cut and fill and the accompanying upgraded haul road. The stability <br />analyses are based upon projected slope configurations and material mechanical <br />properties obtained from material sampling and laboratory analyses. <br />Stability analyses were completed for both the operational and reclaimed configurations <br />of the west portal facility area. During final reclamation of the Bowie No. 1 West Mine, <br />the fill will be removed. The portal cut will be backfilled with this fill and a slope <br />ranging from 2.5:1 to I.5:1 (v:h) will be established. This slope will approximately <br />achieve the post-mine configuration. <br />XI. Revegetation -Rule 4.15 <br />Information pertaining to vegetation baseline may be found on pages 70-75, Part 2.04 of <br />Volume 1, and in the Vegetation Appendix of Volume 9A. Information pertaining to <br />37 <br />