2001-12-11_PERMIT FILE - C1981019 ‎(2)‎

• Permit No: C1981019
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Section_Exhibit Name: Exhibit 07 Item 04 DRAINAGE PLAN FOR COLOWYO COAL CO WORK AREA TIPTON AND KALMBACH INC 1979
• Media Type: D
• Archive: No

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Table 2
Working Arear liaul Road and Loadout Area Ditches
Item Ditches
(1) (2) (3) (4) (5) (b) (7)

Ditch No. 7 8 9 10 11 12
Designation Working Loading Area
Area Haul Road Di version around Loadout
Ditches Type 1 Type 2 Type 3 GossardLoadout Collection Ditches
Maximum Drainage Area (acres) 103 38 81 147 120 7
Design Category Mining Mining Mining Mining Mining Mining
Duration Duration Duration Duration Duralion Duralion
Design Precipitation Frequency (years) 10 10 10 10 10 10
Runoff Coefficient CN78 0.40-O.bl O. d3-0.48 '0.43 0.34 0.52
Rainfall Intensity (in/hr} 0.77 0.77 0.77 0.77 0.77 0.77
Design Flow (cfs) 27 18 35 48 31 6
Average Slope (%) 0.4 5.5 6.0 5.0 0.5 3
Roughness Factor, Manning's n 0.03 0.03 0.03 0.03 0.03 0.03
Design Depth (Feet) 0.9 1.5 1.1 0.9 1.5 0.9
Design Width (feel) 1.0 2.0 4.0 6.0 4.0 1.0
Velocity (ft/sec) 2.3-10.0 9.2 10.2 9.7 3.4 5.9