PERMFILE123757

• Permit No: C1981008A
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Section_Exhibit Name: NH1 TAB 13 ATTACHMENT D SEDIMENTATION POND 004
• Media Type: D
• Archive: Yes

2. Percent Vegetation Cover - The percent of ground surface
• covered by vegetation in undisturbed areas was estimated from
field inspections and aerial photographs.
3. Hydrologic Condition - The hydrologic condition was directly
related to the percent vegetation cover as shown in Table 2.
4. Hydrologic Soil Type - Soil survey maps, as contained in Tab 9
of the current Mine Plan, provides the basis of determining
the hydrologic soil type and soil erodibility factor, "k"
factor (see Table 3).
TABLE 2
SCS Curve Numbers
for
Nucla Mine
Montrose County, Colorado
Hydrologic
Hydrologic Soil Group
Land Use - Vegetation Tvoe Condition B C D
Undisturbed Areas
Cultivated Land Poor 76 84 88
• (Small Grain) Good 75 83 87
Rotation Meadow Poor 75 83 85
(Contoured) Good 69 78 83
Meadow (Riparian) Good 58 71 78
Pasture or Range Poor 79 86 89
Fair 69 79 84
Good 61 74 80
Juniper - Grass Poor 75 85 89
Fair 58 73 80
Upland Sagebrush - Grass Poor 67 80 85
Fair 51 63 70
Residential:
1/8-acre lots Average 85 90 42
1/4-acre lots Average 75 83 87
1/3-acre lots Average 72 81 86
1/2-acre lots. Average 70 80 85
1.0-acre lots Average 68 79 84
Disturbed Areas
Newly Graded Areas Average 86 91 94
4