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Saucor - 2.05.3 haul road connects with the existing Ells Creek road to the lower Elk Geek Mme • portal bench. Both the lower and upper portal benches will be open yard auras. The Elk Geek access road will run between and connect the upper and lower portal benches. At the northwest corner of the upper portal bench, the existing exploration road will be upgraded and utilized as a light-use road to provide access for inspection and maintenance of the slope stabilization area. Additional detail on these roads are provided in Section 2.05.3(3). B. Elk Geek Culvert -Approximately 1,450 feet of the lower portion of Elk Creek has been culverted to minimi~r mining-related hydrologic impacts and facilitate development of required mine suppott facilities for this portion of the Ells Geek channel. OMI will temporarily culvert two segments totaling approximately 1,600 feet of Elk Geek in the middle portion of Elk Geek where the upper and lower portal benches would encroach on the existing stream channel. Stream culverting is designed to minimi~p mining-related impacts and accommodate construction of the required roads and portal benches for the Elk Geek Mute. Additional details on the culvert installations are provided in Section 2.05.3(4). G I'orta] Benches and Roads - In order to provide adequate room for and access to the surface facilities required for the Elk Geek Mme, an upper and lower portal bench and connecting roads will be established in the bottom of Elk Creek. The portal benches and road will vary in width from approximately 50 to 220 feet and will extend approximately 2,200 feet along the canyon bottom. Elk Geek will be culverted at two locations through this area as noted in the previous section. • Available soil material will be recovered from the canyon bottom prior to initiation of cut and fill activities. Soil depths are expected to vary in the canyon bottom, with an average soil recovery depth of 12 inches anticipated. OMI will recover all available recoverable and suitable soils to a maximum depth of 4 feet. In addition to soil materials relocated from the existing Elk Geek soil stockpile, all soil material recovered from the Ells Geek Mute facilities area will be placed in the North Elk Geek soil stockpile for future use in reclaiming mute disturbance areas. The approximately 150,000 cubic yards of fill material required for construttion of the portal benches and roads will be obtained from an upslope slope stabilization area on the west side of Elk Geek Canyon, supplemented by material from mine development in soft-ground (non-coal) materiak. The upslope slope stabilization area is a shallow sutficial slide which is cttrrently moving dowrulope at a very slow rate and toes out in the Ells Geek Canyon bottom Slope stabilization plans focus on removal of material from the upper and central portions of the slide and placement of this material at the tce of the slide as a compacted fill. The proposed surface material removal and fill placement attivities will stabilize the existing slide mass. The pottal bench and road design, including the upslope slope stabilization activities, have been evaluated relative to short-and long-term stability as sumtnatized by the D-Seam Portal Area Slope Stability Report (Abel, 1998), the Slope Stability Analyses for Elk Geek Mme Bench Fills and Soil Stockpile (Montgomery Wauon, 2000), and a supplemental letter addressing establishment of a rock catch bench (Abel, 11/8/00) which are included in Exhibit 2.05-E2, Geotechnical Design and Stability Analyses. • Drainage from the slope stabilisation azea will be controlled through integration of short- and long-term surface stabilization and drainage control measures. Surface stabilization measures will include establishment and maintenance of an upper rock catch bench, grading to establish natural slope breaks and undulations, leaving the surface in a roughened condition, surface revegetation and PR04 2.05-21 Revised May 2001