PERMFILE102806

• Permit No: C1981032
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Doc Name: Diversion Ditch and Sediment
• Section_Exhibit Name: CHAPTER C MINE OPEATION PLAN Appendix A
• Media Type: D
• Archive: No

POND SIZING
. AREA
2 AREA VOL. VOL.
EL (Ft
) (Ft2) AC FT. AC FT.
30.65 0 0 0
938
32 1875 .029 .029
4138
34 6400 .190 .219
9412
36 12425 .432 .651
16150
38 19875 .742 1.393
23262
40 27250 1.082 2.475
Q For Spillway
100 Yr. Upstream -Capacity Channel = 675 - 554 = 121 cfs
100 Yr. Discharge - 10 Yr. Discharge = 22.9 - 9.8 = 13.1 cfs
100 Yr. LW = 48 efs
Total Spillway Capacity = 182.1
•
Crest t? 40.5
Upstream Toe at 30.65
1' Head on Spillway Q = CLH3/2 H = 1 Q = 182.1 C = 3
L = 60.7 Use L = 70'
H=.91'
10 Year 4V.S. El. 7138.46'
Seaiment Elev. 7137.2'
60~ of Sediment Elev. 7136.0'
Outlet Pipe to be 12" 9 CYIP with Gate
Q Max Out = 3 cfs
Capacity of Culverts Under Roads
Required lvlinimum Cover 18"
Try 18" D CMP, HW/D = 2 Q = 11 cfs
Greater Than 10 Yr. - 24 Hr. Flows in Disturbed Area
Satisfies 30 CFR Regs.