Laserfiche WebLink
SOIL LOSS COMPARISON - ROADSIDE NORTH PORTAL <br />RECLAIMED VERSUS BASELINE (SHADSCALE REFERENCE AREA) CONDITIONS <br />The following calculations are presented to determine if untreated drainage from the reclaimed pond 11, <br />CRDA 1 Road, including the top of CRDA-1, and G Substation areas are contributing suspended solids to <br />the stream flow or runoff outside the permit area in excess of pre -mining levels. <br />The baseline data for comparison are considered to be those conditions that exist in the Shadscale <br />reference area. The condition of the reference area and the reclaimed areas are based on 2016 <br />surveys performed by Cedar Creek and Associates. The reclaimed areas are represented by <br />transects 11, 12, 16, 17, 26, 27, 28, 29, 30 in the 2016 survey. <br />Reclaimed Areas, Pond 11 CRDA-1 Road & G Substation <br />Total Perennial Cover+Rock+Litter <br />44.1% <br />52.8% <br />Perennial Cover: <br />Perennial Cover: <br />Grasses, Grasslikes <br />1.6% <br />Forbs <br />1.0% <br />Shrubs <br />18.0% <br />Other - Rock <br />4.8% <br />Litter <br />Other - Rock <br />18.7% <br />Litter <br />1 <br />10.4% <br />Total Perennial Cover+Litter <br />39.3% <br />Cano Shrubs <br />18.0% <br />Ground Cover at Surface39.3-18 Oj <br />21.3% <br />Shadscale reference Area <br />Baseline <br />Total Perennial Cover+Rock+Litter <br />52.8% <br />Perennial Cover: <br />Grasses, Grasslikes <br />10.4% <br />Forbs 1 <br />0.8% <br />Shrubs 1 <br />03% <br />Shrubs, Cacti & Trees <br />6.8% <br />Other - Rock <br />24.1% <br />Litter <br />1 <br />10.4% <br />Total Perennial Cover+Litter <br />28.7% <br />Cano Shrubs+Trees <br />7.1% <br />Ground Cover at Surface 28.7-7.1 <br />21.6% <br />The Universal Soil Loss Equation will be used to calculate the soil loss from the reclaimed areas, <br />and the shadscale reference area to determine if untreated drainage from the reclaimed mine site <br />is contributing suspended solids in excess of premining levels. The following <br />sediment volume calculation is prepared in accordance with U. S. Department of Agriculture, Technical <br />Notes, Agronomy Note #50, dated January, 1977. The maps and figures utilized in the LISLE calculations <br />are obtained from the referenced Agronomy Note #50. <br />The reclaimed areas are broken into three separate areas for evaluation; Pond 11, CRDA-1 and G Substation <br />USING THE UNIVERSAL SOIL LOSS EQUATION <br />R (rainfall) factors are assigned by geographical regions based on weather data furnished by the U.S. <br />Weather Service. R values are based on rainfall amount, time, and intensity In the mountains, R values <br />were computed primarily for valley areas and have been increased to account for run-off from snow melt. <br />The R factor of 30 used for this calculation is derived from an iso-erodent map, presented in the referenced <br />Agronomy Note #50, and is the same for both the reclaimed slopes and the adjacent natural slope. <br />K (soil erodibility) factors are assigned to each soil series and they are used to predict the erodibility of a <br />soil and its tolerance to erosion in relation to specific kinds of land use and treatment. Soils having the <br />highest K value are the most erodible. The K value used for this calculation is derived from data from the <br />U. S. Department of Agriculture Soil Survey, Web Soil Survey, and is based on the soils classification <br />of 15 -Cameo Fine Sandy Loam. SedCad was used to select the X' Factor. <br />The K factor for the soil is 0.24 <br />SL -10 Tab -7, Page 4 03/06/2017 <br />