2019-04-16_REVISION - C1981019 (3)

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RULE 4 PERFORMANCE STANDARDS Rule 4 Performance Standards 4-54 Revision Date: 4/16/19 Revision No.: MR-200 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 1. 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. It must be noted that at the time of planting, conditions were nearly perfect for the emergence of sagebrush (from seed) regardless of field trials being attempted. This circumstance was verified by excellent sagebrush recruitment from all surfaces reclaimed during that year. Therefore, observed results must be interpreted accordingly. Colowyo Mine Specific Plot Construction and Monitoring All plots were constructed in the fall of 2000. Annual monitoring occurred in July of 2001, 2002, 2003 and 2004. Plots were sampled for vegetative cover by species, bare ground, rock and litter. A point-intercept method was used to estimate cover. Within each plot at Colowyo, five 100-m transects were randomly located. Cover data was collected every one meter along each transect (500 cover points per plot). [To avoid loss of data, Cedar Creek commenced monitoring of these plots beginning in 2005 utilizing more stringent scientific methods.] In addition to cover sampling along these transects, CSU estimated shrub establishment and shrub height in each demonstration plot within small quadrats along each transect. At Colowyo, the quadrats were 0.25 m2 and were located every 20 m along the transect for a total of 6.25 m2 per plot. Within each of these quadrats all shrubs were identified to species and heights of individuals were recorded. Monitoring results were provided each year. A final project report was made available by June 15, 2005. The final report detailed the shrub establishment results by treatment method. Final report results also provided a framework for reclamation plan improvements that are designed to enhance native shrub establishment, vegetation community diversity and wildlife habitat, thereby facilitating reclamation and bond release success. [As noted previously, interpretation of these results must be tempered by the fact that the revegetation year of 2000 at Colowyo was an ideal year climatologically for the establishment of sagebrush and other shrubs from seed, regardless of