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Mountain Coal Company L.L.C. West Elk Mine Reface Pile Expansion (RPE) Construction Plan Background Exhibit 70, Volume l OB, of the Mining and Reclamation Permit, addresses the approved final designs for the RPE (TR-79). The Harding Lawson and Associates (HLA) designs depict the pile at final build-out The HLA plans neither describe how the pile will be constmcted, nor temporary sediment control as the pile is being constructed, hence, this construction plan. the construction plan for the RPE will include surveying, clearing vegetation, soils stripping, live haulage/placement, soils storage, ditch construction, refuse pile construction and contemporaneous reclamation Survey The existing RPE outslopes will be surveyed and graded to the required 2.Sh: to lv, prior to soil salvaging, live-hauling/placement, or storing the soil. Vegetation Clearing and Soils Stripping The area where soils will be stripped, will first be cleared. The vegetation material that is cleared will be placed in a windrow and agrinder/mutcher will then be used to reduce the size of the material so it can be easily handled. Approximately 2 ft of soil (5,900 cy) will then be stripped. This soil will belive-hauled directly to the outslopes of the existing pile and placed for reclamation or mixed with the mulched vegetation and placed on the outslopes or moved to Live Subsoil Pile No. 1 or the North Soils Storage Area (NSSA) for future use. Sediment Control Ditches Ditches and the existing RPE Pond will be utilized to control runoff. A riprap ditch will be constructed on the east end of the pile. This ditch will bebuilt-out in it's entirety for this phase of construction The refuse pile, as it is constructed, will build-out to meet this east ditch. The ditch will berip-rapped and tbe D50 size will be crusher + 6"oversized rock. The D50 3-inch designedrip-rap is not practical for construction of this ditch. The ditch will be the clearing limit on the east side of the refuse pile. Another ditch along the hillside /pile interface will be used to direct the flow to the ditch along the east end. This ditch will be temporary and move up the hillside as each lift or series of lifts are added to the pile. The ditch designs incorporated a 100-year 24-hour precipitation event The ditch designs and rip-rap sizing are attached in the Greystone RPE Ditch and Rip-Rap Sizing letter and 1v1ap 54 was changed to include the watersheds and ditches. •