2009-08-13_PERMIT FILE - C1981019A (3)

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variability in depth will be applied in all practical locations to maximize plant community diversity, in both the grazingland and sagebrush steppe targeted areas. 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, and Section 16) 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; < 8 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. Starting in 2005, Section 12 of the Annual Report presents a summary of topsoil stockpile volumes and a table showing the average topsoil replacement depth for each reclamation polygon. 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. When necessary to ensure replacement to the required or desired depths, replacement depths will be staked on the regraded spoil. At this time, Colowyo believes it is impractical to institute a topsoil depth verification program due to the fact that topsoil will be replaced at variable depths and the volume of topsoil will be planned, monitored and verified through load count, time card coding and engineering plan designation of placement of the material on a reclamation unit basis. Overall topsoil balance oversight is performed and reported annually in the Annual Reclamation Report. Even an aggressive topsoil depth sampling program is likely to provide highly variable and misleading results that invite conflict and add an additional layer of potential liability for Colowyo. The overall goal of both the Division and Colowyo is to replace the entire resource in a manner that promotes the likelihood reclaimed areas will meet the success criteria for Phase III Bond Release after the required liability periods and thereby create reclaimed lands that reflect the desired post-mine land use (grazingland and sagebrush steppe). Reapplied topsoil will be left in a rough condition to help control wind and water erosion prior to seeding. Seedbed preparation, other surface manipulation practices and seeding will be completed primarily during the fall months. Contour furrows, approximately 4-6 inches deep at the deepest point and 20-25 inches wide, which have been used on slope areas very successfully during the past several years, will be used to reduce erosion potential, conserve moisture, and maintain site stability until vegetation is sufficiently established. The size of the furrows may be increased if necessary to control erosion, and the distance between the furrows will vary, but will be approximately 10 to 20 feet along the slope. Small rock check dams may also be used where appropriate to aid in control of erosion both prior to seeding 2.05-47 Revision Date: 3/14/08 Revision No.: TR-72