2011-03-25_PERMIT FILE - C1981019A (7)

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The grazingland targeted reclamation blocks will by necessity have thicker layers of topsoil than recent reclamation areas due to reduced volume of topsoil that will be placed on sagebrush steppe areas. Unless Colowyo provides specific justification, the topsoil resource will be placed in a manner that is thin on the ridge tops and gradually increasing in depth to the base of coherent drainages. Large drainage bottom channels that will convey water on a consistent basis will receive little to no topsoil resource as any topsoil placed in these areas will likely be mobilized and washed down the drainage. The full application of seed will still be applied to these areas in order to minimize erosion and allow vegetation to establish in these special locations, adding an additional dimension of potential vegetation community diversity. Colowyo is moving away from applying topsoil in uniform layers and variability in depth will be applied in all practical locations to maximize plant community diversity in areas designated for grazingland. Because the volume of topsoil to be applied to sagebrush steppe targeted areas is much less, and the creation of a seedbed conducive for shrub establishment is of major importance, the variability of topsoil depths within these areas may be limited. However, wherever practical, Colowyo will also make attempts to vary topsoil depths in the Sagebrush Steppe areas as well. Colowyo will ensure proper topsoil resource management through annual analysis of the topsoil balance in stockpiles, the expected areas for the following year's reclamation focus, the total disturbance area, and the results of topsoil stripping activities each year. Because the topsoil resources from the "original" permit areas (East Pit, West Pit, Section 16, facilities, Gossard Loadout, etc.) are for the most part segregated by location from the topsoil generated from the South Taylor area, it will not be difficult to ensure that these resources are reapplied to the general areas from which they came. The same principles apply to both areas (original & South Taylor) regardless of targeted reclamation focus; < 6 inches on ridge tops with variably deeper application down slopes to the bottom of coherent drainages. The major difference between the two areas will be the thickness of reapplied topsoil from mid -slope to the bottom of drainages. Topsoil redistribution criteria specific to sagebrush steppe areas are defined further on in this section. Prior to 2005, essentially all reclamation units were covered with an average of 18 inches of topsoil. One exception to this was the CSU/DMG Shrub study area, which received various treatments of replaced topsoil at 0 ", 6 ", and 18" as described in Section 4.15. From 2005 through 2009, reclamation areas received an approximate average of 8 inches of topsoil as a result of modifications related to TR -62. Reclamation areas from 2010 moving forward (including facilities and the Gossard Loadout area) will utilize variable topsoil depths as described in this section through modifications approved via TR -82, unless otherwise specified (sagebrush steppe and special planting areas). Starting in 2005, Section 11 of the Annual Report presented a summary of topsoil stockpile volumes and a table showing the average topsoil replacement depth for each reclamation polygon, and information on overall topsoil balance. Beginning in reporting year 2010, Section 11 of the Annual Report will present topsoil balances for the original permit area and South Taylor area separately. Topsoil will normally be reapplied by hauling, in trucks, from topsoil stockpiles or from areas where topsoil has been removed for mining advance, to the regraded spoil areas and then redistributed with dozers. Alternate methods may also include placing topsoil on slopes with a dragline followed by redistribution with dozer, or using a scraper to redistribute the topsoil. 2.05 -28 Revision Date: 9/28/09 Revision No.: TR -82