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

Novc:ber 12, 1979
0437-102
Page -3-
• 2. HYDROLOGIC DATA cont'd
d.) Rtmoff Unit Depths in Inches
C. N. 100 Yr. 25 Yr. 10 Yr.
90 1.98" 1.6211 1.0911
92 2.16" 1.79" 1.24"
93 2.25" 1.87" 1.3111
94 2.35" 1.97" 1.40"
95 2.45" 2.06" 1.48"
3. RUNOFF VOLU%ES AND FLOQ3
a.) RLmoff Volum
Mine Area C. N. RLmoff Voliane (Acre Feet)
Sub Area. Acres Sq. Mile 100 Yr. 25 Yr. 10 Yr.
3-1 2.29 0.0035 90 0.38 0.31 0.21
• 3-2 2.57 0.0040 90 0.41 0.34 0.23
4-1 1.00 0.0031 95 0.41 0.34 0.24
4-1A 0.34 0.00053 90 0.06 0.04 0.03
4-2 0.80 0.0013 95 0.16 0.14 0.10
5-1 2.84 0.0044 90 0.48 0.38 0.26
f
5-2 5.16 0.0081 90 0.85 0.70 i 0.47 -73
b.) RLmoff Flows - Type II Storm
Unit
Mine Average Area Discharge Peak
Sub Area % Slope C. N. �acres CFS,Zn Discharges ((7'S
100-Yr 25 Yr 10 Yr
3-1 9 90 2.29 3.7 7.3 0 00 -4.Z
3-2 15 90 2.57 6.3 12.5 10.2 6.7
4-1 2.5 95 1.99 3.0 7.35 4. 9 3.3
4-1A 50 90 0.34 1.1 2.70 2.3 1.5
. 4-2 2.0 95 0.80 1.7 4.16 3.5 2.5
5-1 8.4 90 2.84 5.1 10.1 8.3 5.6
5-2 15 90 5. 16 12 25.9 22.4 16.8
A-3
5 F,