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tends to gravitate downhill, requiring massive efforts to return the material to the upper portions of the pit and to create a stable reclaimed slope. Backfill and grading has been accomplished using the 650 dragline, dozers, and saapers to achieve a stable final postmining configuration. Designed drainage channels and stock ponds are constructed to control and prevent undue erosion while xevegetation is establishing. Once vegetation is re-established, these structures remain as an integral part of the postmining landscape. Topsoil handling is conducted with dozers and scrapers. Live handling of topsoil has only been done on limited basis due to mining area configurations. The majority of the topsoil has been placed in storage stockpiles Eor periods of three yeazs or more before replacement. Topsoil and Spoil Monitoring SCC monitors the salvage, storage, and redistribution of soil and spoil handling operations at the Yoast Mine. Speafic programs include documenting soil recovery, verifying soil redistribution thickness, determining final graded spoil suitability, determining soil fertility, evaluating plant rooting characteristics, and completing an annual soil balance. Sod fertility and spoil quality samples aze collected periodically from soil/spoil samples, which aze randomly located using a 500-foot grid. Post mine soil pits, dug with a backhoe to a five-foot depth, are used to evaluate plant-rooting characteristics and to compare soil/spoil profile data with site- specific revegetation data. These pits are located using an intensity of one pit per twenty-five acres. Post mine soil pits aze placed within reclamation blocks that have been soiled and seeded fot a minimum of three years. Similaz minimum time frames aze used fox monitoring post mine vegetation. The permanent vegetation has generally established suffidendy after three to four years to evaluate interactions between rooting depths and soil/spoil quality. Topsoil Replacement In developing the topsoil replacement plan; SCC gave consideration [o the replacement of varying thicknesses of topsoil within specified portions of the redatnadon area. In addition to areas in which the "standazd" mean replacement thickness (1.4 feet) is conducted, consideration was given to replacement of both "thinner" and "thicker" soils in various locations. The overall vegetation diversity within the reclaimed azeas is enhanced by such vavation in topsoil replacement thickness. Topsoil is replaced with Caterpillar 637 scrapers, at variable replacement depths based on slope grade, aspect, and vegetation type to be planted. SCC is required, by Petmit C-1994-082 and Section 4.06.4(2)(6) of Colorado's Regulations Eor Coal Mining, to document and record the soil replacement thickness for each reclamation block using a minimum sampling intensity of one hole per five acres. The results of the topsoil depth sampling program (147 samples) indicates that the replacement depth ranges from 11 to 36 inches with an overall average of 22 inches. Slopes steeper than 3H:1V require special techniques to improve moisture retention and reduce erosion. "Hummocking", is the process of pock-marking the replaced topsoil with dozer dips, or by track hoe. Revegetation Program Initial consideration in the development of the permanent seed mixes and seedling planting lists included the antiapated reclaimed site conditions and the desired revegetation communities to achieve apost-mining land use for livestock grazing and wildlife habitat. SCC uses appropriate seeding and planting techniques to achieve a rolling post-mine landscape and lasting landform where a Yoart Mrne - 2006 Aeclamatian Amard Nomination page 2