Laserfiche WebLink
• Pos[mining Topography, and designs are discussed in further detail in Tab 20, Backfilling <br />and Grading and Tab 17, Probable Hydrologic Consequences. Seeding the soil stockpiles <br />with an annual grain cover crop or native grasses and fortis, including vigorous rooting <br />and nitrogen fixing plants such as alfalfa, will be done to prevent erosion and also <br />improve the fertility and physical tilth of the soil. The seed mixture, seeding method, <br />and seeding rate for topsoil stockpiles is described in the Revegetation Plan, Tab 22, <br />Table 22-6, the Seed Mixes and Plant Material Lists section of Tab 22, and the Soil <br />Storage section of this tab. The soil removal area at any one time shall be minimized to <br />prevent both wind and water erosion. <br />Peabody does not propose to use any selected overburden materials as soil substitutes or <br />plant seedbed media. This is based on results of the soil survey and soil inventory for <br />Toast. Sufficient quantities of suitable quality soil are available to restore the <br />disturbed areas to the desired postmine land use. Following mining, an average of [.8 <br />feet of suitable soil will be replaced over the final graded spoil medium in the mine area <br />and 1.1 feet of soil wilt be replaced along Haul Roads A and B and the facilities in <br />Section 8. The minimum thickness of soil replaced in the mine area will be 1.0 feet <br />excluding shrub island areas where 0.5 feet of soil will be applied (see Tab 22, Seed <br />Mixes and Planting Lists section). The minimum replaced along Roads A and 0 and the <br />facilities in Section B will be 0.5 feet. <br />No soil will be replaced on those facilities which are to be retained to compliment the <br />final postmine land use. A 20-foot-wide section of Haul Road A and Haul Road B to Station <br />64+00 (10.2 acres) will be maintained. A 3o-foot-aide postmine drainage channel (2.9 <br />acres) will be riprapped. <br />Research over the last ten years has demonstrated that soil depths required for optimum <br />production are related to the quality of the underlying spoil, ui th greater depths of good <br />quality soil needed to restore production on poor quality spoil (U.S. Congress, 1986). <br />Poor quality spoil material may require more than three feet of soil replacement whereas <br />good quality spoil may need less than one foot. In North Dakota, the replacement of one <br />foot of subsoil plus one foot of soil over good quality spoil materials is recommended <br />(Doll et el, 7984). Power et al., (1976) and Barth and Martin (1982) demonstrated that <br />three feet of soi( was necessary for optimum production on sodic spoil. Barth and Martin, <br />7981, shooed fine sandy loam soil depths for optimum production in southeastern Montana to <br />be less than one foot for optimum perennial grass production on nonsaline, nonsodic silt <br />loam spoil. Schuman and others (1980) found that native grass production on reclaimed <br />23 Revised 06/19/95 <br />