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<br />-~ The results are shown below: <br />' Area Cover % CN Number <br />Reference Area 22.67 76.5 <br />' Area 1 18.60 78.5 <br />' Area 2 21.88 77.0 <br /> These CN numbers compare favorably with those listed in the Permit in Attachment <br /> 13-E on pages 4 through 6. <br /> The soil from the area was sent to the CSU Soil Testing Laboratory for an accurate <br /> particle size analysis. The soil sampled was representative of both soils from the <br /> reference area and the reclaimed areas. The results of this analysis are presented in <br />' Table 6. It is seen from the analysis that the soil from the area contains considerable <br />levels of fine material. This exact distribution is used as input in the SEDCAD model <br /> for all three sites. <br />' SOIL ERODIBILITY FACTOR "K" <br />' The soil erodibiliry factor "K", was determined from consultation with the SCS Field <br />Office in Norwood, Colorado responsible for mapping and analysis of the regional <br />soils. The reference area is wmprised entirely of Nyswonger silty clay loam with a <br />' "K" of 0.37. <br />Area 1 is comprised of the following two soil complexes in approximately equal <br />' proportions: <br />' -Pinion/Progresso Loam (Pinion K = 0.37, Progresso K = 0.37) <br />- Pinion/Ustic Torriorthents (Ustic Torriorthents K = 0.15) <br />The weighted average K for this site is therefore: <br />' (3 x 0.37) + jl x 0.15) = 0.315 <br />4 <br />Area 2 is comprised of the Nyswonger silty clay loam and the Pinion/Progresso <br />complex. All of these soils have a "K" of 0.37 therefore the average is 0.37. <br />CP FACTOR <br />' The CP factor in the SEDCAD input is the control practice factor. For rangeland such <br />as that at the New Horizon Mine 1, Table 7 is used in conjunction with the vegetation <br />data to develop the appropriate factors. <br />27 <br />