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Ponds "phe following is a list of the pond designs contained in this scccion: Pond Al - Pond AI collects and treats all the drainage from the loadout area. The pond location and watershed area are shown on flap 3.05-\l4, Drainage and Sediment Control Plan. The pond design is shown o^ il[ap 2.115-\15F. The pond incorporates an 18" riser principal spillway and is designed to treat the 10-years, 24-hour event. The principal spilhvay can also safely pass the peak discharge from the 25-}'ear, 24-hour event while maintaining 1 foot of freeboard. if the principal spilhvay should clog, the existing paved entrance road will act as the emergency spillway with any overflow from the pond crossing the entrance road and tlowing ro the same point where the principal spilhvay dischazges. Pond B - This pond collects and treats all drainage from the main Elk Creek Surface Facilities <\rea. The pond location and watershed area arc shown on Map 2.05-~M4, Drainage and Sediment Control Plan. The pond design is shown on Map 2.05-D45B. Pond C - This pond collects and treats all drainage from the West Valley Fill Development Waste Disposal Area. The pond locazion and watershed area are shown on Map 2.05-M4, Drainage and Sediment Control Plan. The pond design is shown on Map 2.05-MSC. Pond D - This pond collects and treats all drainage from the Elk Creek Mine Surface Facilities Area, including the conveyor corridor ss shown on the drawings. The Principal spillway discharge pipe will have a gated valve. The valve will remain open during ail storm events. The pond location and watershed area are shown on Map 2.05-M4, Drainage and Sediment Control Plan. The pond design is shown on Map 2.05-MSG. Substation- This pond collects and treats all drainage from the Substation No. 3 and C- Pond No. 3 Gulch Ventilation Shaft areas. The pond location and watershed area are shown on i\fap 2.05-M4, Drainage and Sediment Control Plan. The pond design is shown on b4ap 2.05- MSE. Pond F - This is an existing sediment pond that will be modified to collect and treat all drainage from [he disturbed areas of the Hubbard Creek Fansite and access ramp. The pond location and watershed area are shown on b4ap2.05-M4, Hydrology Hubbard Creek Fansite. The pond comprises a 6" PVC principal spillway drop inlet and a secondan 12" CMP straight pipe spillway that contain and treat the 10-year, 24-hour event, as well as an emergency spillway that passes the 25-}'ear, 24 hour event. The pond design is shown on Map 2.05-MSJ, Sedimen[ Pond F Hubbard Creek Fansite. Al] ponds were designed to contain or [rest the runoff resulting from the lll-}'ear, 24-hour event. For all ponds the emergency spillwa}~ is designed to safel}' pass the peak discharge resulting from the 25-year, 24-hour event. The ponds were designed according to the methodologies and assumptions contained in Section 5. All hydrolog}° inputs and resuks are shaven on the SEDCAD printouts contained in Section 10. A summary of the results is shown on the following Tables.