2008-12-04_PERMIT FILE - C1994082 ‎(10)‎

• Permit No: C1994082
• IBM Index Class Name: Permit File
• Doc Date: 12/4/2008
• Doc Name: Pond 012 and Pond 012A Two-Pond System Design ‎(Pgs 13-12.1-149 to 13-12.1-225)‎
• Section_Exhibit Name: Tab 13 Attachment 13-12 Appendix 13-12.1 Part 2
• Media Type: D
• Archive: No

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•
Yoast Mine
Pond ©121012A System
HYDRflLOGlC li~PUT PARAMi=TERS
SEDCAD 4
Channel YPM-7
~
~
Watershed ID -Structure 8 - SWS1
Watershed Area: 36.8
Curve Number:
HYDROLOGIC CURVE AREA
WATERSHED TYPE VEGETATION COVER SOIL GROUP NUMBER (acres)
Reclaimed Fair (30% - 70%) B 71 24.79
Aspen/Mountain Shrub Good (>70%) g 30 8.40
AspenlMountain Shrub Good (>70%) C 47 0.77
Sagebrush Goad (>70%) B 35 2.57
h
b Good (>70%) C 47 0.22
rus
Sage
Total 36.75
CURVE NUMBER 58
SEDCAD 4
Channel YPM-7A
Watershed ID -Structure 8 - SWS2
~Natershed Area: 13.1
Curve Number:
HYDROLOGIC CURVE AREA
WATERSHED TYPE VEGETATION COVER SOIL GROUP NUMBER (acres)
d
l
i Fair (30% - 70%) B 71 13.11
me
a
Rec
Total 13.11
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.
SEDCAD 4
Channel YPM-7
Watershed ID -Structure 8 - SWS1
Sedimentology: k factor
SOILS MAP UNIT/SOILS HYDROLOGIC SOIL AREA
SERIES GROUP k FACTOR (acres)
Reclaimed B 0.32 24.79
34C/D/E/F - Coutis silt loam B 0.37 3.4
46C/D - Splitro loam C 0'24 1.0
l B 0.23 7.9
oam
53C/D/E/F - Winevada
Total 37.1
Weighted k Factor 0.30
TR-37 13-12.1-185 Revised 08108