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18 Right Ventilation Shaft (TR 04-44~ As mine development has proceeded to the north, the distance from existing mine ventilation fan installations has increased to the point where an additional intake ventilation shaft is necessary to maintain effective ventilation of active mining areas. The new ventilation shaft will be located adjacent to Fish Creek in Section 10, TSN, R86W on a low rise above the Fish Creek drainage, as shown on Maps 23 and 236. Development, construction, and installation of the ventilation shaft and fan installation (Figures 30 and 30a) involve the following sequential activities: • Completion of environmental and engineering investigations • Placement of disturbed area mazkers • Marking of stream and wetland buffer zone • Temporary drainage and sediment control measures • Recovery and stockpiling of available topsoil • Installation of drainage and sediment control structures • Construction of an access road and site preparation for shaft pad • Drilling of shaft pilot hole and grouting operations (as necessary) • Construction of temporary power • Construction of shaft collar structure and temporary drilling equipment pad • Shaft boring and casing operations • Erection of escape hoist buildings and equipment and installation of fence(s) • Installation and connection of escape hoist control equipment and systems • Driving of additional entries at the back of the l8 Right longwall panel • Final clean-up and dressing of roads and site pads These activities are briefly described in the following sections. Site-specific investigations required for design and permitting of the new ventilation shaft included a cultural resource survey of potential disturbance areas, soil and foundation characterization as the basis for shaft pad and access road design, and completion of a wetland/AVF survey for the shaft pad and access road. The cultural resource survey was conducted by Metcalf Archaeological Consultants, the engineering soils characterization by Northwest Colorado Consultants, and the soils/wetland/AVF survey by Habitat Management, as described in Section 2.04. The perimeter of all areas affected by surface facilities will be clearly marked before the beginning of surface disturbances. The proposed shaft pad surface area is approximately 280' square (1.8 acres), with a total pad disturbance area (includes cut and fill slopes) of 2.5 acres. The associated access road comdor is approximately 7,100' long, with a finished top width of 24 feet (road corridor 35 feet wide, 5.7 acres). See Exhibit 25T, 18 Right Ventilation Shaft Geotechnical Pavement Design, for details on the road, and Map 24- CDI, anew road profile and cross-section. Approximately 4,400 feet of the access road crosses upland areas, with the remaining 2,700 feet crossing lowland areas where road construction will involve removal of any large vegetation and stripping and stockpiling of other vegetation, topsoil, and organic materials. Given an average topsoil depth of approximately 6" in the upland area and a total road disturbance area of approximately 5.7 acres, approximately 4,600 CY of topsoil will be salvaged from the road corridor, and 2,000 CY from the 2.5 acre pad area. Prior to initiating topsoil removal activities, stream wetland buffer zones will be marked with identifying signs to prevent surface disturbance within buffer zone areas. The topsoil from the road corridor will be windrowed downslope beyond the edge of the 35' road disturbance area, and topsoil from the pad area will be placed in a stockpile adjacent to the shaft pad and within the 100' road corridor, for future reclamation use. The topsoil salvage volumes are indicated on Table 49A. Natural vegetative materials (mulch) incorporated into the topsoil, and seeding with the topsoil stockpile stabilization seed mixture identified on page 2.05-121 will stabilize the windrowed and stockpiled topsoil. MROS-192 2.05-45.3 03/22/05