2008-12-04_PERMIT FILE - C1994082 ‎(23)‎

• Permit No: C1994082
• IBM Index Class Name: Permit File
• Doc Date: 12/4/2008
• Doc Name: 10 Year 24 Hour SEDCAD Demonstration
• Section_Exhibit Name: Tab 13 Attachment 13-17.1 Appendix 13-17.1-A
• Media Type: D
• Archive: No

Yoast Mine
Pond 014 Permanent Feature Demonstration
HYDROLOGIC INPUT PARAMETERS

•
SEDCAD 4
YPM-3-1
Watershed ID -Structure 2 - SWS1
Watershed Area: 26.6
Curve Number;
VEGETATION HYDROLOGIC CURVE AREA
WATERSHED TYPE COVER SOIL GROUP NUMBER (acres)
Reclaimed Fair (30% - 70%) B 71 26.56
Aspen/Mountain Brush Fair (30% - 70%) D 63
W. Wheatgrass/Alkali Sagebrush Fair (30% - 70%) D 89
Total 26.6
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.
YPM-3-1
Watershed ID -Structure 2 - SWS1
Sedimentology: k factor

SOILS MAP UNIT/SOILS SERIES HYDROLOGIC SOIL
GROUP
k FACTOR AREA
(acres)
Reclaimed
35D/F - Aaberg clay B
D 0.32
0.19 26.56
Total 26.6
Weighted k Factor 0.32
Sails series information from Yoast Mine Permit Application Package (see Tab 9, Soil Baseline Study [Nyenhuis,
1994]). Hydrologic Soil Group values are approved Yoast values (see Attachment 13-12, Table 13-12.2). The soil
erodibility factor, "k-Factor", values are presented in Attachment 13-12, Table 13-12.2.
YPM-3-1
Watershed ID -Structure 2 - SWS1
Sedimentology: Control Factor
CONTROL AREA
LAND USE CONDITION COVER TYPE VEGETATION FACTOR (acres)
Undistrubed Aspen/Mtn. Brush 25% canopy, 80% 0,042
ground cover
Herbaceous 60% ground cover 0.042
Reclaimed Reclaimed 60% ground cover 0.042 26.56
Total 26.6
Weighted Control Factor 0.042
The Control Factor values are approved Yoast Mine values as presented in Attachment 13-12, Table 13-12.3. The
values were originally presented in Renard, et al. (1997) Predicting Soil Erosion by Water: A Guide to Converation
Planning with the Revised Universal Soil Loss Equation (RUBLE), Agricultural Handbook 703, U.S. Department of
Agriculture as reported in Warner et al. (1998) as reported in Warner et al. (1998).
TR-37 13-17.1-A.14 Revised 02/08