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Allyn Davit Mine Safety and Hea/[h Adminithakon October 70, 2003 Page 7 OMLLC does not operate a coal preparation plant and the only "coal processing" that occurs is crushing and screening of the raw coal to meet coal shipment specifications. Given this consideration, coal refuse materials from the Elk Creek Mine consist of a mixture of coal, carbonaceous material, and rock. These materials aze generated by underground development activities (developing entries to access coal reserves and provide ventilation), separated from the coal by the coarse screen (grizzly) in the dump station, or originate from non-coal materials falling from mine walls (ribs) or the mine roof (top). Chemical analyses of mine xoof and floor materials, which are representative of the coal refuse materials, indicate that the sampled materials are not potentially acid- or alkali-forming, or toxic-producing. Facility Design and Construction Topographic constraints (i.e., a rapidly narrowing and steepening drainage valley that severely limit potential material placement quantities) preclude expansion of the existing West Valley Coal Refuse Facility. OMLLC has therefore, completed preliminary designs for a new coal refuse facility. The proposed facility, designated as the II West Coal Refuse Facility, is located in the second ephemeral drainage to the west of the existing West Valley Coal Refuse Facility, as shown on the Facilities Map, (Map 1). The proposed coal refuse disposal facility will be designed, operated, and reclaimed in essentially the same manner as the present facility. The proposed coal refuse facility will consist of the following, as shown on the Facilities Map, (Map 1): • Designed drainage and sediment control system (diversion ditches, collection ditches, and sedimentation pond and outlet structures)to handle surface drainage from the facility area • Coal refuse haul road and associated drainage structures (ditches and culvens) • Light-use road and associated drainage structures (ditches and culverts) to access the sedimentation pond • Refuse pile underdrain to handle any surface water that may infiltrate under or percolate through the pile (prevents saturation of foundation and lower portion of pile) • Refuse pile, constructed as a series of designed refuse fill benches Facility design, pemvtting, development, operation, and reclamation have or will involve the following sequential activities: • Complete geologic and geotechnical field investigations within the facility footprint, with detailed investigations in the refuse pile and pond embankment foundation areas • Complete required cultural resource, soils, spring and seep, wetlands, and 'T'hreatened and Endangered (T&E) species investigations in project area • Complete hydrologic and hydraulic design calculations for design of surface drainage system and refuse pile underdrain • Design concrete pond embankment