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Because of a number of factors, both natural and as a result of applied current technology, reclaimed <br />plant communities will be dominated by stabilizing herbaceous vegetation which will provide a stable <br />and productive beginning point from which vegetational change (succession) may move toward plant <br />communities that include to greater or lesser degrees, the presence of woody plants and forbs. <br />Standards, therefore, must be derived which not only take into account premining native vegetation <br />conditions, but also consider the inherent reclaimed community characteristics resulting from applied <br />technologies and realistic successional (community development) rates achievable in reclaimed areas <br />in the semiarid west after so little time as ten years. <br />For the II -W mine (including the II -W South Extension area), the five dominant affected types in the <br />permit area include aspen woodland, mountain brush, steep mountain brush, sagebrush /snowberry, <br />and western wheatgrass /alkali sagebrush. These types are well distributed across the undisturbed <br />north, east, south, and west portions of the permit area. Based on consideration of maximum <br />disturbance impacts, the following minimum acreages of the five major types will be available for <br />comparison sampling. aspen woodland - 250 acres, mountain brush - 710 acres, steep mountain brush <br />- 150 acres, sagebrush /snowberry - 460 acres, and western wheatgrass /alkali sagebrush - 150 acres. <br />These acreages represent the minimum acreages to be used; however, whenever possible, comparisons <br />will consider the maximum undisturbed area available at any given time as the sampling universe. <br />Quantitative cover and production data from these types will serve as the basis for developing <br />weighted averages for cover and production comparisons in the II -W area (including the South <br />Extension area). The pre - mining vegetation types within the final disturbance area have been <br />reevaluated to determine the final percentages to be used for calculating weighted averages. <br />The following percentages of vegetation types that were present in the current disturbance area (as of <br />2008) prior to mining (as determined by baseline studies) are: <br />Aspen - 11.0 %, Mountain Brush - 34.5 %, Steep Mountain Brush - 12.8 %, Sagebrush /Snowberry <br />31.3 %, and Western Wheatgrass /Alkali Sagebrush - 10.4 %. <br />As a block of reclaimed is delineated for bond release, then pre - mining vegetation types will be <br />evaluated to determine if these percentages need to be adjusted for that particular block. <br />TR -65 45 Revised 9/09 <br />