2023-07-27_REVISION - C1981038 (10)

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Waste Pile pond, an access road which leads to the old waste disposal pile and sedimentation ponds 1 and 2 and an access road which leads to sedimentation ponds 3 and 4 from BLM road leading to the old Converse Mine. The five light use roads include three roads at the East Mine, named east, central and west roads, which provide access for hydrologic and subsidence monitoring, a road leading from the main East Mine facilities fan bench to the explosives storage area and a road leading to the West Mine fan area. At the main East Mine facilities area, there is one haul road, the asphalt paving of which has now been removed, leading from the now reclaimed security post at the turnoff from the Stevens Gulch road to the crushing and screening bench, also reclaimed. The mine site haul road and access roads were constructed prior to the enactment of SMCRA and the Regulations of the Colorado Mined Land Reclamation Board for Coal Mining, therefore the haul and access road embankments and road cuts were not constructed according to the specifications set forth in Rule 4.03. Alternative specifications may be authorized by the Division if the applicant can demonstrate through appropriate geotechnical analysis that the existing road embankments have a minimum safety factor of 1.25, and that the road cuts have a minimum safety factor of 1.5 or that a lesser safety factor will not result in significant environmental harm or harm to the public health or safety (4.03.1(3)(c)(i) and (3)(d)(ix), and 4.03.2(3)(C)(i) and (3)(d)(ix)). The operator demonstrated that the haul road and access roads are stable and would continue to meet the performance standard. The demonstration was supplied in a report(Phase II - Geotechnical Stability, by Merrick and Company) submitted in response to stipulation No. 14 of the 1981 Orchard Valley Mine (Bowie No. 1 Mine) Permit, which is included in Volume 6 of the PAP. The Division approved the alternative road specifications based on this demonstration. The reclamation plan approved in Technical Revision No. 28 allows for the retention of access roads and the associated terraces.The presently permitted haul and access roads will be narrowed to a 16-foot width within the 20-foot wide terrace corridor. The reclamation plan requires that all other terraces be reclaimed. The operator had committed to removing the asphalt between Stevens Gulch and the crushing and screening level and performing finish grading of the road,which has been done. In August 1986, the operator submitted a permit revision application (PR-02) to construct new portal facilities, named the West Mine, in the East Roatcap Creek Valley. This application proposed the construction of a new portal facility and haul road, because the existing portals at the Orchard Valley Mine,now the Bowie No. I Mine,had been rendered unusable by an underground coal mine fire. The applicant proposed to upgrade an existing public access road to serve as a coal haul road to the proposed portal bench. The geotechnical specifications for the West Mine road are found in Volume 6, prepared by Golder Associates, consultant to the operator. This appendix presents the results of geotechnical investigations, stability analyses and detailed engineering design for the portal bench cut and fill and the accompanying haul road. The stability analyses are based 20