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potential for sediment to leave the area. Water can potentially drain along the north side of Pond F and light-use road railroad embankment. The azea is well vegetated and has arock-check dam, which will additionally filter surface runoffprior to dischazge. Overland Belt West -This area is comprised of some 0.5 acres between the haulroad embankment and railroad tracks west of the Haulroad C rail crossing. Estimated runoff for the 10 yr/24 hr event would be some 0.03 acre-feet from this azea, and will be treated by means of a rock filter. This should be more than sufficient, given that drainage for the azea is neazly static. Hautroad C Topsoil Pile -Covers approximately 0.3 acres between the haulroad and FoideI Creek, and is located across from Pond C. Runoff from the area is filtered by established vegetative cover. TCC will also inscribe a berm and install rock filters to further treat the anticipated 0.01 AF of runoff for the 10-yt 24-hr event from this azea. Scoria Storage Area ('I'R 05-451- A portion of the former Haul Road A northwest of Pond C is used as a storage area for the scoria and gravel materials used in maintaining mine roads. The Scoria Storage azea covers approximately 0.87 acres. The surface of this area is graded so that most minor drainage is naturally contained. Runoff from any significant storm event drains to the south and east, where an existing berm routes runoff flows to a sump and collection ditch designed to treat the runoff from a 10-yeaz, 24-hour storm event. From this ASC, the ditch dvects drainage flows through swell-established vegetative filter to FoideI Creek The SAE demonstration for the Scoria Storage Area is provided in Exhibit 8U. Storage and Training Area (Trudv's Corner - TR 05-451- An area located east of Pinnacle Peak and northeast of Pond A previously disturbed and used in conjunction with historic surface mining activities (Trudy's Comer), is currently utilized as a materials storage and training area. This area encompasses approximately 0.78 acres. Drainage from this azea flows to the west to an existing drainage ditch along the Pond A access road, then approximately 0.15 miles through the vegetated ditch and swell-established vegetative filter to Pond A. An SAE demonstration documenting the effectiveness of this drainage configuration for the Storage and Trauvng Area is provided in Exhibit 8U. 7 North Escape Shaft -Covers 1.82 acres of disturbance and is located in the SE 1/4, Section 20, TSN, R86W, 6th P.M. on Cochetopa Loam (a "C" soil). SAE demonstrations have characterized four areas: the north outslope, the east and west outslopes, the south side of the topsoil pile, and the pad, which inwrporates drainage from the north side of the topsoil pile, the cutslope, the berm, the pad; and road drainage from the road. Sediment control will be achieved by seeding and mulching the pad outslopes, the cutslopes, and the topsoil pile, and by placing straw bale dikes or a silt fence below each of these locations to prevent off-site migration of sediment prior to vegetative stabilization. Vegetative filters will provide adequate sediment detention to achieve effluent limitations following a 10-yeaz 24-hour storm event for these locations. Rock check darns will be installed at the southeast corner of the topsoil pile and below a riprapped Swale descending the northeast comer of the outslope. Peak flows from a 10-year 24-hour storm are 0.06 cfs, 0.03 cfs, 0.42 cfs, and 1.59 cfs for the north outslope, east or west outslope, north side of the topsoil pile, and pad, respectively. EMD Ventilation Shaft -Covers approximately 2.66 acres of disturbance and is located in the NW'/.SE'/. Sec. 14, TSN, R86W, 6th P.M. on Routt loam (a "C" soil). SAE demonstrations have characterized three areas: the east side of the east topsoil pile; the south and west sides of the southwest topsoil pile; and other topsoil slopes and the benches and cut and fill slopes of the facility itself. Sediment control will be achieved through installation of an upland clean water diversion ditch, by seeding and mulching the topsoil piles and cut and fill slopes with 2 tons/acre of straw, and by graveling the pads and roads with sufficient gravel to achieve 80 percent gavel cover. Vegetative filters will provide adequate sediment detention to achieve effluent limitations following a 10-yeaz, 24-hour storm event. Peak flows from the design storm are 0.05 cfs, 0.27 cfs, and 1.96 cfs for the east side of the east topsoil pile, the south and west sides of the southwest topsoil pile, and other topsoil slopes and the benches and cut and fill slopes of the facility, respectively. TR O5~5 2.05-82 Revised -January 2005