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slope of 0.50 percent and a flow velocity equal to 1.9 feet per second. • Riprap is provided in Section B. Refer to Figure 2, Sediment Collection Ditches - Design Detail, for design details and channel characteristics. Collection Ditch No. 2 (CD-2j CD-2 is located along the north and east perimeter of the raw and clean coal stockpile areas as shown on the Drainage and Sediment Control Map, (Map 20). Runoff from the north and east portions of the stockpile area is collected by CD-2 and routed directly into the west end of Sedimentation Pond No. 1. CD-2 is designed as one segment with a channel slope of 5.0 percent and flow velocity equal to 4.1 feet per second. The peak flow calculated for the 10-year, 24-hour event is 3.39 cubic feet per second. Refer to Figure 2, Sediment Collection Ditches - Design Detail, for design details and channel characteristics. . Collection Ditch No. 3 (CD-31 CD-3 is located along the south and west perimeter of the raw and clean coal stockpile areas as shown on the Drainage and Sediment Control Map, (Map 20). Runoff from the south and west portions of the stockpile area is collected by CD-3 and routed to a yard catchment basin which routes the runoff via 18-inch CMP to Sedimentation Pond No. 1, as shown on the Drainage and Sediment Control Map, (Map 20). CD-3 is designed as one segment with a channel slope of 0.03 percent and a flow velocity equal to 0.5 feet per second. The peak flow calculated for the 10-year, 24-hour event is 2.09 cubic feet per second. Riprap is not required in CD-3. Refer to Figure 2, Sediment Collection Ditches - Design Detail, for design details and channel characteristics. Access Road Collection Ditch . The access road collection ditch is located along the northern edge of the access road as shown on the Drainage and Sediment Control Map, (Map 20). 94 R Revised - December, 1991