2010-10-07_PERMIT FILE - C1994082

• Permit No: C1994082
• IBM Index Class Name: Permit File
• Doc Date: 10/7/2010
• Doc Name: Post Mining Channels SEDCAD Results/Channel YPM-1 to YPM-8
• Section_Exhibit Name: Tab 13 Attachment 13-12 Appendix 13-12.3
• Media Type: D
• Archive: No

Yoast Mine
Postmine Channel Design
HYDROLOGIC INPUT PARAMETERS

SEDCAD 4
Channel YPM-2
Watershed ID -Structure 2 - SWS1
Watershed Area: 4.9
Curve Number:
HYDROLOGIC CURVE AREA
WATERSHED TYPE VEGETATION COVER SOIL GROUP NUMBER (acres)
Reclaimed Fair (30% - 70%) B 71 4.3
Shrub
i
t Gcod (>70%) B 30 0.6
a
n
Aspen/Moun
Total 4'9
CURVE NUMBER 66
Vegetation cover conditions presented in Tab 10, Vegetation, Attachment 10-1, 1990/1992 Vegetation
Baseline Report, Yoast Study Area (ESCO Associates, 1993). Approved Yoast Mine curve numbers are
presented in Attachment 13-12, Postmining Drainage and Sediment Control ,Table 13-12.1. Values were
adapted from Urban Hydrolcgy for Small Watersheds, Technical Release No. 55, Soil Conservation Service,
1986.
•
•
TR-37
13-12.3-17
Revised 02/08