2012-07-10_PERMIT FILE - C1981041 ‎(5)‎

• Permit No: C1981041
• IBM Index Class Name: Permit File
• Doc Date: 7/10/2012
• Doc Name: Soils Loss Comparison Roadside North Portal Cameo Refuse Disposal Areas and Cameo Borrow Areas
• Section_Exhibit Name: Tab 14 Appendix 14-13
• Media Type: D
• Archive: No

SOIL LOSS COMPARISON - CAMEO REFUSE DISPOSAL AREA #1 - POND 6
RECLAIMED VERSUS BASELINE (ADJACENT) CONDITIONS
The following calculations are presented to determine if untreated drainage from the reclaimed Cameo Refuse
Disposal Area #1 is contributing suspended solids to streamflow or runoff outside the permit area in excess of
premining levels. Pond 6 collects run off from the Cameo Refuse Disposal Area #1 (see attached Appendix page
A14- 31 -20).
The baseline data for comparison are considered to be those conditions that exist in the adjacent area. The adjacent
area for vegetative cover comparison is the Shadscale reference area (see attached Appendix page A14- 13 -18). The
vegetation on the reclaimed and adjacent areas are presented in detail in Cedar Creek Associates 2010 Revegetation
Evaluation and are summarized below.
Shadscale Reference Area
Baseline
Total Perennial Cover +Rock
30.85%
Perennial Cover:
Grasses, etc.
4.10%
Forbs
0.80%
Shrubs
2.70%
Trees
0.00%
Other - Rock
19.87%
23.25%
Total Perennial Cover +Rock
Total Perennial Cover+Rock
30.85%
Litter
19.60%
14.05%
Total Perennial Cover +Rock
Total Perennial Cover +Rock +Litter
44.90%
Canopy (Trees and Shrubs
2.70%
Cameo Refuse Disposal Area #1
Reclaimed
Total Perennial Cover +Rock
40.89%
Perennial Cover:
Grasses, etc.
10.7%
Forbs
0.87%
Shrubs
9.47%
Trees
0.00%
Other - Rock
19.87%
Total Perennial Cover +Rock
40.89%
Litter
19.60%
Total Perennial Cover +Rock
+Litter
60.49%
Canopy (Trees and Shrubs)
9.47%
The Universal Soil Loss Equation will be used to calculate the soil loss from the reclaimed mine site and the
adjacent baseline area to determine if untreated drainage from the reclaimed mine site is contributing suspended
solids in excess of premining levels. The following sediment volume calculation is prepared in accordance with
U. S. Department of Agriculture, Technical Notes, Agronomy Note #50, dated January, 1977. The maps and
figures utilized in the USLE calculations are obtained from the referenced Agronomy Note #50.
USING THE UNIVERSAL SOIL LOSS EQUATION
R (rainfall) factors are assigned by geographical regions based on weather data furnished by the U.S. Weather
Service. R values are based on rainfall amount, time, and intensity. In the mountains, R values were computed
primarily for valley areas and have been increased to account for run -off from snow melt. The R factor of 20
used for this calculation is derived from an iso- erodent map, presented in the referenced Agronomy Note #50,
and is the same for both the reclaimed slopes and the adjacent natural slope.
K (soil erodibility) factors are assigned to each soil series and they are used to predict the erodibility of a
soil and its tolerance to erosion in relation to specific kinds of land use and treatment. Soils having the highest
K value are the most erodible. The K value used for this calculation is picked from the U.S. Department of
Agriculture Soil Survey, Douglas Plateau Area, and is based on the soils classification; Torriorthents. The K
factor of 0.37 is the same for the adjacent and reclaimed areas.
PR -5 A14 -13-1 02/12