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 BORROW AREA #2 -POND 11
RECLAIMED VERSUS BASELINE (ADJACENT) CONDITIONS
The following calculations are presented to determine if untreated drainage from the reclaimed Cameo Borrow
Area #2 is contributing suspended solids to streamflow or runoff outside the permit area in excess of premining
levels. Ponds 11 collects run off from the Cameo Borrow Area #2 (see attached Appendix page All 4- 13 -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 Greasewood reference area (see attached Appendix page
All 4- 13 -19). The vegetation on the reclaimed and adjacent areas are presented in detail in Cedar Creek Associates
2010 Revegetation Evaluation and are summarized below.
Greasewood Reference Area
Baseline
Total Perennial Cover +Rock
18.9%
Perennial Cover:
Grasses, etc.
4.85%
Forbs
0.15%
Shrubs
11.25%
Trees
0.00%
Other - Rock
2.60%
Total Perennial Cover +Rock
18.85%
Litter
31.201/6
Total Perennial Cover +Rock
+Litter
50.1%
Canopy (Trees and Shrubs
11.3%
Cameo Borrow Area #2
Reclaimed
Total Perennial Cover +Rock
38.2%
Perennial Cover.
Grasses, etc.
0.8%
Forbs
5.6%
Shrubs
27.5%
Trees
0.0%
Other - Rock
4.3%
Total Perennial Cover +Rock
38.2%
Litter
18.5%
Total Perennial Cover +Rock +Litter
56.7%
Canopy Trees and Shrubs
27.5%
The Universal Soil Loss Equation will be used to calculate the soil loss from the reclaimed area 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 tables 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 -13-8 02/12