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Topsoil <br />Topsoil performance standards are found in Section 4.06 of the PAP (Volume 1 for the East Pit, <br />West Pit, Section 16 Pit, Facilities Area and Gossard Loadout and Volume 12 for South Taylor). <br />Additional information on the soil types can be found on Maps 5, 5A, 513, 5C and 6 of the PAP. <br />Eighteen inches of topsoil was replaced on all graded sites through 2005 except for approved <br />exceptions. One exception is the Section 11 Pit, where 12 inches of topsoil was placed. With <br />the approval of TR -62 on 29 May 2006, the topsoil replacement depth for all post 2005 <br />remaining reclamation in the East Pit, West Pit, Facilities area and Gossard Loadout was reduced <br />to eight inches. The topsoil replacement depth for the South Taylor Pit, the West Taylor Fill, the <br />East Taylor Fill and all additional disturbances associated with Permit Revision 02 will be 12 <br />inches. <br />A variable topsoil replacement depth was approved with TR -82 (September 2009), and <br />implementation began in 2010. As described in the PAP, the general plan is to place topsoil in <br />thinner layers (average of four inches) near ridge tops, to encourage the development of a <br />Sagebrush Steppe, and to place deeper topsoil on steeper slopes. Steeper slopes are generally <br />considered greater than 10 percent, and on these slopes a grassland environment is encouraged. <br />The topsoil in areas outside of the South Taylor area averages six inches of depth near the top of <br />the slope and 10 to 14 inches of depth further down the hillside. In the South Taylor area, the <br />planned depth of topsoil on the steeper slopes is even deeper than in other areas (up to four feet <br />depending on the slope length and topsoil balance considerations). <br />Revegetation <br />Native and introduced forbs and grasses will be drill seeded or broadcast seeded (on steep <br />slopes). Shrub and tree species are also drill seeded or broadcast seeded, based on terrain. <br />Revegetation efforts will be monitored to determine vegetative success as described in <br />Section 4.15 of the PAP. Chisel plowing and terrace or contour furrows are the preferred <br />methods of seed bed preparation. Mulching is not in general use at the Mine. <br />Colowyo has made considerable efforts in recent years to establish shrubs and trees in the <br />reclaimed areas. In particular, TR -84 addressed Stipulation 13 and provided a detailed plan for <br />the procedures and possible locations for the tall mountain shrub and aspen planting areas in the <br />South Taylor Pit. <br />TR -82 provided a detailed plan for the variable replacement depth of topsoil on the backfilled <br />and re- graded portions of the West Pit and South Taylor Pit. Related to the variable topsoil, <br />Colowyo also designed an area - specific seeding program. On steeper slopes (over 10 percent) <br />deeper soil is placed and the area is seeded to grassland for post- mining grazing and for erosion <br />control. On flatter slopes the areas were covered with four inches of topsoil (on average) and <br />seeded to sagebrush steppe. The sagebrush steppe areas are targeted to provide Sage Grouse <br />habitat. <br />Proposed Decision and Findings of Compliance January 2012 <br />Permit Renewal 06 Page 124 <br />