1987-12-01_PERMIT FILE - C1981017 ‎(163)‎

• Permit No: C1981017
• IBM Index Class Name: PERMIT FILE
• Doc Date: 12/1/1987
• Doc Name: Mine Portal Areas Drainage and Sediment Control Plans
• Section_Exhibit Name: Chapter II Attachment 1 to Appendix II-B-7
• Media Type: D
• Archive: No

5. POND DESIGN CRITERIA
a.) Mi ni n 4n Req red Storage Capacities
• Annual 3-Year 10 Year minil m
Mine se-di t Sediment Flood Total
Sub Area Storage Storage Storage*
of of of of
3-1 0.028 0.084 0.21 0.29
3-2 0.046 0.138 0.23 0.37
4-1 0.19 0.570 0.27 0.84
4-2 0.002 0.006 0.10 0.11
5-1 0.017 0.051 0.26 0.31-
5-2 0.064 0.192 0.47 0.66
k a) 100 % 10-year flood
b) 100 % 3-year sediment yield
b.) M xin!n Discharge Capacity Requirements for Outlets, Emrgency
Spillways and Ditches.
Mine 25-Year 10-Yea?- Mine Effluent,
Sub Area Discharge, Discharge,
cfs cfs cfs
3-1 6.0 4.0 0.5
3-2 10.2 6.7 0
4-1 7.2 4.8 0
4-2 3.5 2.5 0
5-1/5-2 30.7 22.4 0
A--6
59