2010-11-19_PERMIT FILE - C1980007 ‎(36)‎

• Permit No: C1980007
• IBM Index Class Name: Permit File
• Doc Date: 11/19/2010
• Doc Name: Surface Facilities Area and Water Tank Site
• Section_Exhibit Name: Exhibit 66 SAE Lone Pine Water Tank
• Media Type: D
• Archive: No

area. For adjacent undisturbed areas,
slope angles were
drawn from the area
immediately adjacent to the reclaimed
•
or revegetated area. Slope lengths for
undisturbed areas were selected from the
same transect line as the undisturbed slope
angle. Undisturbed slope measurements were selected to be close
(in length) to those
identified within the reclaimed or revegetated areas. The slope angles and lengths for
the analysis are provided below.
Location
Slope Length
Slope Angle
Lone Pine UDWP
130'
21 0
Lone Pine Topsoil Pile
90'
26 0
Lone Pine Staging Area
70'
35 0
Lone Pine UDWP undisturbed area
100'
14 0
Lone Pine Topsoil Pile undisturbed area
100'
14 0
Lone Pine Staging Area undisturbed area
70'
35"
Water Tank reclaimed area
75'
16 0
Water Tank undisturbed area
75'
16°
COVER AND MANAGEMENT FACTOR (C)
The' cover and management factor in the USLE accounts for the effect of plant and
litter cover on the ground surface in reducing erosion by intercepting raindrops and
reducing direct contact with the soil. For the varying vegetation types such as that at
the West Elk Mine, Table 1 was used in conjunction with the 1997 vegetation data to
develop the appropriate factor values.
The mean total vegetation cover of the Underground Development Waste Pile was
43.50 percent, comprised largely of sod- forming and bunch grasses with spreading
bases. Additional significant cover is provided by the much branched and spreading
forbs, Achillea lanulosa (western yarrow) and Polygonum douglasii (knotweed) with a
combined cover of 6.00 percent. These types of vegetation provide significant cover
contacting the ground surface. Grasses provide 84 percent of the mean total vegetation
cover, with the remaining 16 percent provided by forbs. Litter contributes 50.00
percent ground cover. The UDWP reclaimed area falls within the "no appreciable
canopy category of Table 1. Assuming 94 percent ground cover (43.50% vegetation
cover, 50% litter, and 0.50% rock), the C factor for the UDWP reclaimed area is
estimated at 0.0035.
At the revegetated Topsoil Pile, vegetation cover was 60.67 percent. As with the
UDWP area, cover was predominantly grasses (49.33%), and forbs-(9.33%). Litter
_ provided 33.33 percent ground cover. As with the UDWP area, the C factor was
selected from the "no appreciable canopy" category of Table 1. Percent g round cover
was 94 percent, composed of grasses and forbs, indicating a C factor value of 0.0035..
The Staging Area at the Lone Pine Gulch Surface Facilities Area was situated on a
steep north - facing slope. Vegetation cover was more sparse on the upper areas of the
n