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<br />8. On the top of Page 2.05-48 Colowyo states that "...topsoil will be left in a rough <br />condition..." Please provide additional detail regarding the methods that will be <br />used to ensure that the topsoil is either left in a roughened state or roughened prior <br />to seeding. This practice is especially important in light of the fact that scrapers <br />are used for topsoil replacement at the Colowyo Mine, since scrapers contribute a <br />great deal of compaction to the topsoil. <br />Colowyo's Response: <br />In the case of scrapers, dozers cross-rip along slope contours at intervals of about 50-75 <br />feet to provide additional surface roughness. Also, contour furrows are almost always <br />put in place when scrapers are utilized to minimize any sheet flow from the topsoil <br />surface. Due to the specific equipment used for the Sagebrush Steppe areas, topsoil will <br />be left in a more smooth condition to ensure proper seeding depth as described in the <br />text. Any topsoil put into final position with a dozer will by practice be in a state of <br />"rough condition ". Previous roughening efforts at Colowyo have been extreme, leading <br />to difficulties in placing seed at biologically viable depths. The addition of more contour <br />furrows will reduce sheet flow and moderating the roughness will allow a greater <br />percentage of seed to germinate and provide ground cover that will also alleviate rilling <br />and sediment control issues. As Coloywo transitions into areas of steeper slopes, density <br />of cross ripping will be tightened to increase surface roughness and more contour <br />furrows will be used to break up the slopes and minimize sheet flow conditions and <br />reduce any concentration offlow from rain/snowmelt events. <br />9. Although variable topsoil replacement for the West Pit and South Taylor Pit is the <br />primary focus of TR-82, there is no mention of the topsoil replacement activities <br />in the East Pit, the Gossard Loadout or the facilities area. It is assumed that since <br />these areas are not specifically mentioned in the text that the topsoil in these areas <br />will be replaced in a uniform depth of eight inches, as approved in Technical <br />Revision 62. Please include a discussion of the topsoil replacement depth(s) and <br />method(s) that will be used in the East Pit, Gossard Loadout and facilities area <br />reclamation. <br />Colowyo's Response: <br />As discussed from the beginning of this process, the original permit area which <br />includes the West Pit, East Pit, Section 16 and the South Facilities will be <br />managed as one area requiring an average of eight inches of topsoil to be <br />replaced. The Gossard Loadout (North Facilities) area has been previously <br />discussed and will be addressed at a later date as agreed. Since the South Taylor <br />area was anticipated to yield an average of approximately 19.5 inches of topsoil, <br />and the stockpiles are separate from those of the original permit area, it was <br />agreed that those resources would be segregated in order to "put it back where it <br />came from ". Figure 2.05-5 identifies the areas within the East Pit, West Pit, <br />Section 16, South Facilities, and South Taylor that will be targeted for Sagebrush <br />Steppe establishment or Grassland.