2014-04-03_REVISION - C1982057 (4)

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Steep Mountain Brush Reference Area Allowable All -Hit Herbaceous Cover' = 16.4% Western Wheatgrass /Alkali Sagebrush Reference Area Allowable All -Hit Herbaceous Cover' = 24.6% 1 Herbaceous cover adjusted by subtracting noxious weeds and annual/biennial plant cover in excess of 10% of the remainder 90% of the Cover Standard = 0.9 *[0.110(76.5 %) +0.345(35.9 %) +0. 313(29.2 %) +0.128(16.4 %) +0.104(24.6 %)] _ 31.1 The mean allowable all -hit herbaceous vegetation cover sampled in 2012 for the bond release area was 46.1 percent, which exceeds the 31.1 percent required cover standard; thus demonstrating successful revegetation with respect to the cover standard. Note that the mean allowable cover value for the bond release area is slightly different than the report table in Attachment E. The adjusted Phase II area dropped a sample from the data set but did not affect adequacy or the outcomes presented here. A reverse t -test of the assertion that the 2009 Phase II bond release block allowable cover is indistinguishable from 90% of the standard is as follows: tc =(46.1 — 31.1)/(13.7/sgrt 59) =8.4 Since critical t = 0.848 (one - tailed, alpha = 0.2, 58 df) and t, is greater than this critical value, reclamation success for Phase II is demonstrated. Species Diversity and Composition Mandatory Test A, no single species comprise greater than 60% relative cover in the bond release area. Test results show that the most abundant single species, alfalfa, was 21.61 % relative first -hit cover, well below the 60% threshold of concern. Hence Mandatory Test A is passed for the 2009 sampling data. • Alternative Test B, the Total Species Density test, the following is calculated for the bond release area: Probability adjusted density standard Mean Reference Area Species Density —1.15s Mean total species density in the bond release area = 25.6 species per 100 sq. m. Mean species density (Area - weighted) in the 5 reference area types = 25.3 species per SL -5 -7