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equal to the 90 percent confidence interval for the corresponding revised woody plant <br />counts, revegetation will be deemed adequate relative to woody plant density. <br />TR -45 resulted in the warm season grass revegetation success standard being revised as found <br />on revised Permit page 2.05.27: <br />The final warm season grass vegetation success standard for all of the reclaimed areas <br />at both the Southfield Mine and Southfield Loadout will consist of the number of warm <br />season grasses having relative percent composition values greater than 3 percent as <br />identified in the 2013 and 2014 Phase III revegetation monitoring reports for the four <br />currently approved reference areas. The final warm season grass species diversity <br />revegetation success criteria will be based upon a weighted average factor, based upon <br />the acreages of the four currently approved reference areas in calculating the final <br />warm -season diversity revegetation success standard. <br />Southfield Mine Reference Areas. <br />Allowable Cover. Across all three Reference Areas located at the Southfield Mine Area, the <br />calculated weighted average "allowable plant cover" value is 35.31 % with a weighted average <br />standard deviation of 6.64. Thus, the ultimate weighted average revegetation success standard <br />for "allowable plant cover" at the Southfield Mine area would be 31.78 % (35.31 % x.90 = <br />31.78 %). Application of the sample adequacy formula to these weighted average data means <br />that the number of samples needed to characterize the parameter of "allowable plant cover" for <br />these three combined reference areas at the 90 % confidence interval is 5.9 samples. A total of <br />76 plant cover samples were collected on these combined three reference areas, and the sample <br />adequacy formula found in the CDRMS regulations, requires 5.9 samples. <br />The weighted average perennial herbaceous forage production across these three combined <br />reference areas yields a value of 23.48 g/1/4m2 or 836.8 pounds of air-dry forage per acre, with <br />a weighted average standard deviation of 9.49. Application of the sample adequacy formula to <br />these forage production data means that the number of samples needed to characterize the <br />parameter of perennial herbaceous forage production for these three combined reference areas <br />was 27.3 samples. <br />Southfield Mine Area Reclamation. <br />Allowable Cover. Using the Permit reclamation weighting factors of 79.8 % for grassland or <br />Refuse Pile Reclamation and 20.2 % for the Pinyon/Juniper or Portal Reclamation and the <br />corresponding areas associated with the Vento Portal Reclamation and Corley Reclamation <br />found on Map 1, Southfield Mine Reclamation Map results in the Corley Reclamation <br />having a weighting factor of 10.79 % and the Vento Portal Reclamation having a weighting <br />factor of 9.41 %. Application of the weighted averaging technique to "allowable plant cover" <br />across the three combined reclamation areas located at the Southfield Mine would yield an <br />"allowable plant cover" value of 46.78 % with a weighted average standard deviation of 14.28. <br />Application of the sample adequacy calculation to these data means that the number of samples <br />needed to characterize the parameter of "allowable plant cover" for these three reclamation <br />areas would be 5.6 samples. <br />A total of 76 plant cover transects were sampled on the three combined Southfield Mine <br />Reference Areas and since sample adequacy was achieved (Nm=5.6) and since 45 plant cover <br />transects were collected on these three combined reclamation areas and since a sufficient <br />number of samples were collected to characterize the parameter of "allowable plant cover" at <br />26 <br />