2011-07-01_PERMIT FILE - C1982057A ‎(6)‎

• Permit No: C1982057A
• IBM Index Class Name: Permit File
• Doc Date: 7/1/2011
• Doc Name: Postmine Drainage Channel Design
• Section_Exhibit Name: Tab 20 Attachment 20-1
• Media Type: D
• Archive: Yes

Seneca II-W Mine
005 Gulch Postmine Channel Design
HYDROLOGIC INPUT PARAMETERS
SEDCAD4
WATERSHED ID
005 Gulch
S5-SWS-1
Watershed Area:
20.4 acres
Curve Number:
WATERSHED VEGETATION HYDROLOGIC CURVE AREA
TYPE COVER SOIL GROUP NUMBER (acres)
Reclaimed Fair: 30-70% B 70 10.1
Mixed Brush Fair: 30-70% B 48 7.3
Mixed Brush Fair: 30-70% C 57 3.0
Total 20.4
CURVE NUMBER: 60
SEDCAD4
WATERSHED ID
005 Gulch
S5-SWS-2
Watershed Area:
42.4 acres
Curve Number:
WATERSHED VEGETATION HYDROLOGIC CURVE AREA
TYPE COVER SOIL GROUP NUMBER (acres)
Reclaimed Fair: 30-70% B 70 42.4
Total 42.4
CURVE NUMBER: 70

•
SEDCAD4
WATERSHED ID
005 Gulch
S5-SWS-3
Watershed Area:
7.6 acres
Curve Number:
WATERSHED VEGETATION HYDROLOGIC CURVE AREA
TYPE COVER SOIL GROUP NUMBER (acres)
Reclaimed Fair: 30-70% B 70 7.6
Total 7.6
CURVE NUMBER: 70
Curve number (CN) values used are approved Seneca II-W CN values (North Area; see Table 13-1 ).
Values were adapted from Urban Hydrology for Small Watersheds, Technical Release No. 55 (TR-55),
Soil Conservation Service, 1986.
Revised 08/07
TR-59 20-1.11