2010-10-07_PERMIT FILE - C1994082 ‎(2)‎

• Permit No: C1994082
• IBM Index Class Name: Permit File
• Doc Date: 10/7/2010
• Doc Name: YPM-9 to YPM-24, Dragline Deadhead Route Postmine Channel
• Section_Exhibit Name: Tab 13 Attachment 13-12 Appendix 13-12.3 Part 2
• Media Type: D
• Archive: No

YOAST MINE
Postmine Channel Designs -Channel YPM-11
HYDROLOGIC INFU7 PARAMETERS
SEDCAD 4
Structure 3 - SWS1
Watershed W-10 (YPM-10)
Watershed Area: 61.9
Curve Number:
HYDROLOGIC CURVE
WATERSHED TYPE VEGETATION COVER SOIL GROUP NUMBER AREA (acres)
Aspen/Mountain Brush Good (>70%) D 48 0.4
Steep Mountain Brush Good (>70%) C 65 0.77
Steep Mountain Brush Good (>70%) D 73 1.18
Sagebrush Fair (30%<x<70%) C 63 0.37
laimed
R Fair (30%<x<70%) C 71 59.2
ec Total 61.9
CURVE NUMBER 71
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 Hydrology for Small
Watersheds, Technical Release No. 55, Soil Conservation Service, 1986.
•

TR-37 13-12.3-141A Revised 02/08