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At the main East Mine facilities area, there is one haul road, the asphalt paving of which <br />has now been removed, leading from the now reclaimed security post no. 1 at the turnoff <br />from the Steven's Gulch road to the crushing and screening bench, also reclaimed The <br />mine site haul road and access roads were constructed prior to the enactment of SMCRA <br />and the Regulations of the Colorado Mined Land Reclamation Board for Coal Mining and <br />at that time the haul and access road embankments and road cuts were not constructed <br />according to the specifications set forth in Rule 4.03. Alternative specifications may be <br />authorized by the Division if the applicant can demonstrate through appropriate <br />geotechnical analysis that the existing road embankments have a minimum safety factor of <br />1.25, andthat the roadcutshave a minimum safety factor of 1.5 or that a lesser safety factor <br />will not result in significant environmental harm or harm to the public health or safety <br />(4.03.1(3)(c)(i) and (3)(d)(ix), and 4.03.2(3)(C)(i) and (3)(d)(ix)). <br />The operator demonstrated that the haul road and access roads are stable and would <br />continue to meet the performance standard. The demonstrationwas supplied in a report <br />(Phase II - Geotechnical Stability, by Merrick and Company) submitted in response to <br />stipulation No. 14 ofthe 1981 Orchard Valley Mine (Bowie No. I Mine) Permit, andwhich <br />is included with the Permit Application in Volume 6. The Division approved the <br />alternative road specifications based on this demonstration. <br />The reclamation plan approved in Technical Revision No. 28 allows for the retention of <br />access roads and the associatedterraces. The presently permitted haul and access roads will <br />be narrowed to a 16 foot width within the 20 foot wide terrace corridor. Thereclamation <br />plan requires that all other terraces be reclaimed. The operator had committed to removing <br />the asphalt between Steven's Gulch and the crushing and screening level and performing <br />finish grading of the road, which has been done. <br />In August 1986, the operator submitted a permit revision application to construct new <br />portal facilities, named the West Mine, in the East Roatcap Creek Valley. This application <br />proposed the construction of a new portal facility and haul road, because the existing <br />portals at the Orchard Valley Mine, now the Bowie No. 1 Mine, had been rendered <br />unusable by an underground coal mine fire. The applicant proposed to upgrade an existing <br />public access road to serve as a coal haul road to the proposed portal bench. <br />The geotechnical specifications are found in Volume 6, prepared by Golder Associates, <br />consultant to the operator. This appendix presents the results of geotechnical <br />investigations, stability analyses and detailed engineering design for the portal bench cut <br />and fill and the accompanying haul road. The stability analyses are based upon projected <br />cut slope configurations and material mechanical properties obtained from material <br />sampling and laboratory analyses. <br />Stability analyses were completed for cross sections chosen at road stations believed to <br />represent potentially critical slope stability situations along the proposed upgraded haul <br />road. As a result of this slope stability analysis, the operator amended its original proposed <br />road cut slope configurations to use a Hilfiker wall, or equivalent, retention system. The <br />retention system was to be utilized as depicted on Sheet 7 of 10 of the Golder Associates <br />report, entitled "Haul Road (1)," to reduce the unretained cut slope heights to a maximum <br />19 <br />