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The 27.9% (see Appendix A) ground density cover of the affected area (Exhibit 5, Permit) correlates with a CN value of 85 over Carracas Loam soils and 81 over Nunn Loam soils areas (Figure S-3, Juniper-grass). 1 1 L~ 1 Other CN values specific to areas of the demonstration are developed under the respective area discussions. 2.8 Control Practice Factor The SEDCAD+ Model considers the sediment loss from an area with a given cover and conservation practice to that of a field in continuous fallow by introduction of a Control Practice (CP) Factor. In this demonstration, protective cover in contact with the ground surface is taken as perennial grasses and fortis, shrub and brush under 0.5 meter in height, litter and rocks. In this demonstration, Antelopebrush, Gray rabbitbrush, and Broom snakeweed encountered on the site in the 1996 Vegetation Survey is considered as canopy (over 0.5 meter in height). In the Exhibit 5 Vegetation Survey, all trees, shrubs and sub- shrubs are considered as canopy. Fortis are considered to provide ground protection equivalent to "weeds" in Table S.~c of the SEDCAD+ documentation. A CP factor of 0.019 is developed from Table S.Sc of the SEDCAD+ documentation for the alluvial toor reference area in the Table 2.8-1. Table 2.8-1 Alluvial Valley Floor Reference Area CP Value % Ground Cover In Contact With Ground Surface No appreciable $0 81 ~ 95-100 canopy I CP Factors 100% grass' j 0.013 ~ ~ 0.003 78% grassZ 0.020 0.019 0.005 100% weeds' 0.043 0.011 ' Table 5.~ SEDCAD+ documentation. Z Includes grasses, litter and rocks, 1996 Vegetation Survey. A conservation practice of "Permanent Pasture, Rangeland, Idle Land, and Grazed Woodland" was selected as representative of the Rangeland Reference Area. A CP factor for the rangeland reference area of 0.031 is developed in Table 2.8-2. Page 7 of 34, 7 Oct 96