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<br />X. Climatological Information and Air Resources - <br />Ru es 2. 4. 2. 5.4 2 2. an <br />Peabody Coal Company has submitted climatological baseline information in <br />Tab 8 (Volume V) and initially approved Emission Permit No. 82R0258 in the <br />Tab 14 of Volume IX of the permit application. In addition, a discussion of <br />the climatological conditions found at the site is contained in the <br />description of the environment portion of this document. The applicant has <br />provided the required information and the operation is in compliance with the <br />requirements of this section. <br />XI. Topsoil - Rules 2.04.9, 2.05.3(5), 2.05.4(2}(d), and 4.06 <br />The permit area is occupied by three soil orders; Mollisols, Entisols, and <br />Aridisols. The presence of these three orders is characteristic of the soils <br />found in steep, semi-arid regions of Northwestern Colorado. These orders <br />represent soils that grade from recently developed soils with minimum horizon <br />development to more developed soils with well developed diagnostic horizons. <br />Specific soil types within these orders occur on predominantly three types of <br />parent material-land form combinations, name]y: 1) upper side slopes, ridges, <br />and swales of sandstone residuum; 2) toe slopes, side slopes, rounded ridge <br />tops of shale residuum and colluvium; and 3) toe slopes, side slopes, ridges, <br />and escarpments of sandstone and shale. Among the 22 soil types occurring <br />within the permit area, major topsoil salvage limitations include clay <br />textures, high coarse fragment content, steep slopes, shallow bedrock, <br />salinity, and alkalinity. <br />Peabody Coal Company strips topsoil in single lifts once the woody vegeta tion <br />has been removed. Topsoil will be re-distributed immediately on regraded <br />areas when possible or stockpiled in designated storage areas. The amount to <br />be stockpiled depends on pit advance, season of the year, and reclamation <br />activities taking place at the time of salvage. Stockpiled topsoil is placed <br />in stable areas and protected from wind and water erosion by planting of a <br />quick-growing vegetative cover. Single lift stripping mixes different soil <br />horizons and thereby dilutes heavy clay concentrations encountered in various <br />subsoils. <br />During the adequacy review of the permit application, concern was expressed <br />over the applicants proposal to not salvage topsoil from the Royal Variant <br />soil type (mapping unit 103) which was rated as fair and appeared to have a <br />salvageable depth of at least 20 inches on portions of the mapping unit. <br />The applicant responded with additional information indicating that although <br />small isolated areas of map unit 103 contain suitable fair rated topsoil, <br />salvage of the material without contamination by unsuitable subsoils is <br />largely prevented due to a combination of steep slopes, equipment limitations, <br />operator safety, soil variability within the mapping unit, and the presence of <br />coarse fragments randomly exceeding 35 to 50 percent of the soil volume. The <br />Division recognized these limitations, but believed that small portions of the <br />unit could be safety salvaged with the types of earthmoving equipment to be <br />employed by the operator. In response to this concern, the applicant <br />committed to include map unit 103 in the topsoil resource quality control <br />program described on pages 9-30 and 9-31 of the amended permit application. <br />- 41 - <br />