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Generally, those soils which have a very high percentage of coarse fragments (greater than <br /> 35 percent by volume), very shallow bedrock (0 to 10 inches), and shallow ground water <br /> (less than 1 to 2 feet), have little suitable topsoil to be salvaged. No suitable topsoil <br /> is available to be salvaged from Map Unit 810. This soil has unsuitable levels of calcium <br /> carbonate at the soil surface. Additionally, no topsoil is available to be salvaged from <br /> existing roads, ponds, residences, or farmyards. Topsoil salvage from Units 1EW and 808 <br /> will only be possible if premine ground water levels are lowered and the soils have <br /> sufficient time to dry prior to disturbance. Otherwise, significant and uncontrollable <br /> topsoil degradation would occur during salvage due to compaction and destruction of <br /> structure. <br /> Topsoil Salvage Depths. Topsoil is beneficial for increasing infiltration, improving the <br /> seedbed and rooting medium for germination and plant establishment, enhancing nutrient <br /> cycling, and serving as a source of seed, rhizomes, and root cuttings that can promote <br /> species diversity. Topsoil depth requirements on mined lands are site specific. Often, <br /> the quality of spoil material to be covered by topsoil is the major controlling factor <br /> (Schuman and Power, 1980; Barth and Martin, 1982). <br /> The suggested salvageable depths of topsoil material presented in this section are based <br /> on laboratory data and extensive field observations, and represent only the most suitable <br /> sources of topsoil material. No unsuitable sources of topsoil will be salvaged and used <br /> during reclamation activities. The following section summarizes topsoil salvage depths, <br /> volumes, and characteristics /by map unit for the Nucla East disturbance area. <br /> 1E - Travessilla-Pinon Channery Sandy Loams Complex. This map unit complex occurs on <br /> well-drained, gently sloping to moderately steep upland hills and ridges in the northeast <br /> portion of the permit area. Small areas of sandstone ledgerock are included within this <br /> map unit. This complex is comprised of 60 percent Travessilla and 25 percent Pinon with <br /> 10 percent rock outcrop and 5 percent Torriorthent inclusions. The Travessilla and Pinon <br /> soils are both very shallow (less than 10 inches) to shallow (10 to 20 inches) over <br /> sandstone bedrock. Travessilla soils lack significant profile development while Pinon <br /> soils have a structurally developed subsoil calcic horizon. <br /> These soils are fair to poor sources of topsoil being shallow to very shallow and <br /> typically having 5 to 35 percent coarse fragments throughout the soil profile. The mean <br /> depth of suitable soil for Travesilla, based upon 8 profiles, and Pinon, based upon 4 <br /> profiles, is 9 and 12 inches, respectively. <br /> 21-19 Revised 04/11/88 <br />