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The access roads into the site have approximately 9" of 6" minus pit run and 4" of 1" minus base coarse. The • material was graded and crowned to facilitate drainage off of the roads. The upper road is approximately 900 feet in length and the lower road is approximately 450 feet in length. The top width of the roads is approximately 15 feet. Upland drainage is diverted around the site. The fan buildings were painted to blend in with the surrounding area. The fence constructed around the perimeter ofthe site is used to keep animals out of the area. The power line comes in from the northeast from an existing YVEA site. The sediment control system utilizes a diversion ditch, seeding and mulching topsoil pile, cut and fill slopes, grading road and pad, and the adjacent vegetation filter. NW Mains Ventilation Shaft and Thickener Underflow Protect (TR 01-39) As mine development has proceeded to the north, the distance from existing mine ventilation fan installations has increased to the point where an additional ventilation shaft and fan installation are necessary to maintain effective ventilation of active mining areas. The new ventilation shaft and surface fan installation, will be located approximately 900 feet north of Fish Creek in Section 17, TSN, R86W on a low rise above the Fish Creek drainage, as shown on Maps 23 and 23B. Development, construction, and installation of the ventilation shaft and fan installation involves the following sequential activities: • Completion of environmental and engineering investigations • 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 • Construction and extension of power distribution line • Construction of shaft collar structure, temporary drilling equipment pad and fan foundations • Shaft boring and casing operations • Erection of fan enclosure and control buildings and installation of fence(s) • Installation and connection of fan, drive, and control equipment and systems • Driving of additional entries in the Northwest Mains • 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 access road and power line crossing of Fish Creek. The cultural resource survey was conducted by Metcalf Archaeological Consultants, the engineering soils characterization by Northwest Colorado Consultants, and the wetland/AVF survey by Habitat Management, as described in Section 2.04. The proposed shaft pad area is approximately 280' square (1.8 acres) and the associated access road corridor is approximately 3,800' long with a finished top width of 22 feet (road corridor 30 feet wide). See Exhibit 25 S, NW Mains Ventilation Shaft Access Road Design, for details on the road. Approximately 2,000 feet of the access road crosses upland areas, with the remaining 1,800 feet crossing lowland areas where road construction will involve removal of any large vegetation and placement of geotextile and road fill over the in-place soils. Given an average topsoil depth of approximately 6" in the upland area and a total disturbance area of approximately 1.4 acres, approximately 1,1 1 I CY of topsoil will be salvaged from the road corridor, and 1,452 CY from the pad. The topsoil TR 01-39 2.05-45 8/10/01