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Sample Adequacy Calculations <br />Sample adequacy of total all -hit allowable herbaceous vegetation cover was achieved in BRB -2b as well <br />as each of the reference areas except Aspen Woodland in 2014 (see below and Table B -4). Thus, for <br />Aspen Woodland, the alternative of using the upper 90% probability value of the mean was exercised. It <br />can be assumed that the CDRMS minimum sample size (15) is intended to produce a reasonable <br />estimate of population variance [which is true based on experience]. Given this, then data from the 15 <br />samples of the Aspen Woodland Reference Area likewise establishes a reliable estimate of population <br />variance. Using this variance estimate, the maximum possible value of mean all -hit allowable herbaceous <br />cover (with 90% confidence) was taken to represent the contribution of the Aspen Woodland Reference <br />Area to establishment of the cover performance standard (see below). Details of the calculation of <br />allowable herbaceous cover for each area are provided in Tables F -1 through F -6. <br />2014 Assessment of the BRB -2b for Compliance with Phase 11 Performance Standards <br />COVER <br />As described above, in 2014, sample adequacy based on all -hit values was achieved for BRB -2b and <br />each of the reference areas. <br />Calculation of 90 percent of the cover performance standard appropriate for 2014 sampling is <br />demonstrated below. <br />Aspen Reference Area Allowable All -Hit Herbaceous Cover' = 99.94 %2 <br />Mountain Brush Reference Area Allowable All -Hit Herbaceous Cover' = 42.07% <br />Sagebrush Reference Area Allowable All -Hit Herbaceous Cover' = 33.13% <br />Steep Mountain Brush Reference Area Allowable All -Hit Herbaceous Cover' = 26.60% <br />Western Wheatgrass/ Alkali Sagebrush Reference Area Allowable All -Hit Herbaceous Cover' = 46.72% <br />' Herbaceous cover adjusted by subtracting noxious weeds and annual /biennial plant cover in excess of 10% of the remainder. <br />2Upward adjusted as described above and in Table B -4. <br />90 percent of the Cover Standard = <br />0.90` [0.11(99.94 %) +0.35(42.07 %) +0.31(33.13 %) +0.13(26.60 %) +0.10(46.72 %)] = 39.71 <br />The mean allowable all -hit herbaceous vegetation cover sampled in 2014 BRB -2b was 40.14 percent, <br />exceeding 39.71 percent, which is 90 percent of the cover performance standard (see also Figure H -1 a, <br />Table B -1). This direct comparison of reclaimed area mean to the standard is allowed under DBMS rules <br />(CDMG 2005 revised rule, 4.15.11 (2)(a)) when sample adequacy has been demonstrated for the <br />16 <br />