2012-06-20_PERMIT FILE - C2010089A (7)

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Production. The results obtained from the sampling of 50 production transects on this area are summarized in Appendix Table 2.04.10 -7, Sagebrush - Production. This table shows that the average total herbaceous forage production on this site equaled 3.46 g/1 /4 m or 123.3 pounds of air dry -dry forage per acre. Perennial grasses contributed 1.78 g/1/4 m or 51.44 percent of the herbaceous forage produced on this area. Perennial forbs, contributed 1.68 g/1/4 m or 48.56 percent of the herbaceous forage production on this area. Evidence of the relatively poor ecological condition of the Big Sagebrush vegetation type is found in the NRCS Soils Survey by comparing our monitoring data with that reported to occur on the Semi Desert Loam and Pinyon - Juniper ecological sites, which correspond to the soils types found in these Sagebrush areas. In the Soils Survey, herbaceous forage production for these two ecological sites is reported to average 600 and 300 pounds of forage per acre, respectively. This comparison suggests that the Big Sagebrush vegetation type is producing only approximately between 20.6 and 41.1 percent of its ecological potential. This comparison documents the relatively poor ecological condition of this vegetation type. The locations of the 50 production transects sampled on the Big Sagebrush vegetation type are shown on Map 2.04.10 -1, Permit Area Vegetation Map. The sample adequacy calculations in Appendix Table 2.04.10 -2, New Horizon North Mine Area - Sample Adequacy Calculations, document that the number of samples required to describe this site at the 90 percent confidence interval was 187.7 transects. Shrub Density. The shrub density counts obtained from the 15 belt transects sampled in this area are summarized in Appendix Table 2.04.10 -8 Sagebrush - Shrub Density. The average shrub density was determined to equal 56.53 shrubs per one hundred square meters or 2,287.8 shrubs per acre. Basin Big Sagebrush, Rubber Rabbitbrush and Fourwing Saltbush were the most commonly encountered shrubs. The locations of the 15 shrub density transects sampled on the main block for this reclaimed site are shown on Map 2.04.10 -1, Permit Area Vegetation Map. Examination of the sample adequacy calculations in Appendix Table 2.04.10 -2, North Mine Area - Sample Adequacy Calculations, reveals the number of samples required to describe the shrub density on this area at the 90 percent confidence interval was 40.0 transects. IRRIGATED PASTURE This vegetation type is found on those areas which are actively irrigated and are found down slope of the existing irrigation ditches. The Irrigated Pasture is vegetation type is the third largest plant community type found within the proposed NHN Mine permit area (Map 2.04.10 -1 - Permit Area Vegetation Map). This area covers an area approximately 59.68 acres in size and accounts for nearly 18.52 percent of the proposed permit area. Section 2.04.10 Page 13 November 2011