2008-12-04_PERMIT FILE - C1994082 ‎(2)‎

• Permit No: C1994082
• IBM Index Class Name: Permit File
• Doc Date: 12/4/2008
• Doc Name: 10 Year, 24 Hour Postmine SEDCAD Demonstration
• Section_Exhibit Name: Tab 13 Attachment 13-3A.1 Appendix 13-3A.1-A
• Media Type: D
• Archive: No

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YOAST MINE
Pond 10 System
HYDROLOGIC INPUT PARAMETERS
SEDCAD 4
Structure 11 - SWS1
batershed ID: Channel YPM-22
Watershed Area: 15.8
Curve Number:
HYDROLOGIC
CURVE
WATERSHED TYPE VEGETATION COVER SOIL GROUP NUMBER AREA (acres)

Aspen/Mountain Brush Good >70%
( ) C 41 4.66
Aspen/Mountain Brush Good (>70%) D 48 3'71
Sagebrush Gccd (>70%) C 47 1.62
ir (30% - 70%)
F B 71 5.8
Reclaimed a
15.8
Total
CURVE NUMBER 54
SEDCAD4
Structure 11 - SWS2
Watershed ID: Channel YPM-22
~Matershed Area: 1.4
Curve Number:
HYDROLOGIC CURVE
WATERSHED TYFE VEGETATION COVER SOIL GROUP NUMBER ARE:4 (acres)
Reclaimed Fair (30% - 70%) B 71 1.4
Total 1.4
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, Sail Conservation Service, 1986.
SEDCAD 4
Structure 11 - SWS1
Watershed ID: Channel YPM-22
~~--
Sedimentology: k factor
HYDROLOGIC SOIL

SOILS MAP UNITlSOILS SERIES
GROUP
k FACTOR AREA (acres)

8
0.32 5.80
Reclaimed g 0.37 6.3
X8D/E!F - Winevada - Splitro complex

35C/D - Aaberg clay D 0.1 g 1.4
2 3
D 0.20
103 - Ustorthents-Cryoborolls complex 15.8
Total
Weighted k Factor 0.31
C
TR-37
13-3A.1-A.39
Revised 02/08