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• scrapers to maneuver at the bottom of that slope, topsoil will be removed by being pushed <br /> downhill with a dozer, picked up with scrapers, then stockpiled or transferred directly to <br /> regraded areas. <br /> A two-lift topsoil operation will be utilized for the two primary premine irrigated <br /> hayland/pastureland soil types (30C and D70B), whereby the "A" and upper "B" horizons are <br /> salvaged separately from the lower "B" and "C" soil horizons. Two-lift topsoil salvage <br /> will be used within Map Unit D70B as warranted by additional premine soil sampling. This <br /> method of topsoil removal is desirable at Nucla East because these irrigated <br /> hayland/pastureland soils are dominantly moderately deep to deep (20 to 60 inches), soil <br /> profile development is moderate (relatively thick, dark colored, near mollic "A" and upper <br /> "B" horizons overly argillic "B" horizons), and landscape slopes are gradual which helps <br /> to improve equipment mobility and efficiency. The two-lift principle will promote surface <br /> fertility and will help to quickly reestablish•nutrient cycling in postmine soils because <br /> the upper layer includes stable aggregates, dynamic organic matter, and micro-organisms <br /> critical to plant nutrient relationships. Up-to-date topsoil handling techniques utilized <br /> in combination with suitable spoil replacement and topsoil/spoil scarification are more <br /> effective in reestablishing minesoil productivity than 50 years of succession on poor <br /> quality minesoils (Schafer, et al., 1979). The salvageable topsoil from Map Units 30C and <br /> D70B will primarily be utilized, whenever feasible, in postmine irrigated hayland and <br /> pastureland areas. <br /> The Barx soil (a component of Map Unit D70B) has been determined to be prime farmland by <br /> the Soil Conservation Service (see Tab 9, Attachment 9-5, Document 9-5-1). There are 15.0 <br /> acres of Map Unit D70B identified as prime farmland (i.e, currently irrigated and utilized <br /> as hayland) within the proposed permit area (see Exhibit 12-3, Operations Plan - Nucla <br /> East and Exhibit 9-6, Soil Types, Sample Locations, and Topsoil Salvage Depths). <br /> Specific soil map units (1E, 1EW, and 808) at Nucla East are more suited for one-lift <br /> topsoil salvage because they are very shallow to shallow, have little profile development, <br /> and/or are excessively stratified. The salvageable topsoil from these units will <br /> primarily be utilized, whenever feasible, in postmine dry pastureland areas. One-lift <br /> topsoil will generally be isolated from the two-lift topsoil during all soil handling <br /> operations. However, this material may also be utilized as first lift topsoil or second <br /> lift subsoil in postmine irrigated pastureland areas. <br /> 21-26 Revised 08/19/88 <br />