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that has often bE;en observed during the 20 years of interim monitoring at this mine. Young <br />revegetation that does not meet allowable cover standards in year two or four has been observed <br />to eventually do so as it passes into the upper end of the ten-year liability period. <br />Herbaceous Production <br />Calculation of 90 percent of the production performance standard appropriate for 2006 sampling <br />is as follows: 90 percent of the Herbaceous Production Standard set by the weighted average of <br />the measured production of the Mountain Brush Reference Area and the Sagebrush Reference <br />Area = 0.90[0.83(542.5) + 0.17(1149.1)] = 581.1 oven-dry Ib/ac. As can be seen in Figure 2, all <br />reclaimed area:. sampled far exceeded 90 percent of the herbaceous production standard. The <br />data in Figure 2 in the right-hand side of the paired columns are corrected for "allowable" <br />production (i.e. subtracting production from annual /biennial species that exceed 10% of total <br />production). <br />Woody Plant Density <br />Figure 3 graphically presents "background" shrub density averages for reclaimed areas sampled <br />in 2007. As can be seen, all areas exceeded the 100 stem per acre background standard. <br />Although shrub concentration areas within the 2003 and 2005 reclamation areas will not be <br />identified until :such time as a bond release test is undertaken, it would appear at this early date <br />that the occurrence of shrub density levels over 900 stems per acre (90% of the shrub <br />concentration standard of 100 stems per acre) is likely in from 10 to 20 % of the areas (well <br />exceeding the required 5%). <br />Species Diversity and Composition <br />With regard to Mandatory Test A, that no single species comprise greater than 60% relative <br />cover, reference to Tables 1 and 4 shows that in both the 2003 and 2005 reclamation the most <br />abundant single species (intermediate wheatgrass) varies from 27 to 35% relative first hit cover, <br />far below the 60% threshold of concern. Hence Mandatory Test A) is passed. <br />With regard to Alternative Test B), the Total Species Density test the following is calculated for <br />BRB-3: <br />Mountain Brush (MB) reference mean species density: 30.2 species per 100 sq.m. <br />mean - 1.15*s = 30.2 - 1.15 (6.5) = 22.7 <br />Sagek~rush (SB) reference mean species density: 33.9 species per 100 sq.m. <br />13 <br />