2008-09-29_PERMIT FILE - C1981019A (13)

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RULE 4 PERFORMANCE STANDARDS Parameter Plot la Plot 2 Plot 3e Plot 4 Plot 5e CEC meq/100g 26.8 22.1 22.9 27 23.3 % Sand 41 51 48 39 41 % Silt 23 23 23 23 25 % Clay 36 26 29 35 35 Texture clay loam sandy clay loam sandy clay loam clay loam clay loam aPlot 1 = 18 inches of topsoil, strip seeding in alternate rows. bPlot 2 = 6 inches of topsoil and surface manipulation, seeded with native shrubs and low competitive forbs. °Plot 3 = 6 inches of topsoil, strip seeding in alternate rows. dPlot 4 = Non-topsoiled spoil, strip seeding in alternate rows. 'Plot 5 = Non-topsoiled spoil, seeded with unpalatable native shrubs and low competitive forbs and grasses. To evaluate the impact from wildlife browse, elk proof fencing was constructed on one-half of each treatment. Colowyo Mine Specific Field Trial At the Colowyo Mine, field trial treatments to be evaluated include five plot treatments as shown on Figure 4.15-1. 1. 18 inches of live-haul topsoil over spoil with strip seeding. The strip seeding would include a strip of native shrubs and native low-competitive forbs that would alternate with a strip of native grasses, forbs, and shrubs. The proposed seed mixtures for this treatment are presented in data provided in the 2005 Annual Report. 2. 6 inches of live haul topsoil over spoil and seeding with native shrubs and low-competitive native forbs. Include some surface manipulation to create depressions for enhanced soil moisture conditions. The proposed seed mixture for this treatment is presented in Table 2.05-7. 3. 6 inches of live-haul topsoil over spoil with strip seeding. 4. Non-topsoiled spoil with strip seeding. 5. Non-topsoiled spoil seeded with relatively unpalatable native shrubs, low-competitive native forbs, and low-competitive native grasses. Rule 4 Performance Standards 4.15-5 Revision Date: 6/23/08 Revision No.: MR-91