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The permit area is occupied by three soil orders; Mollisols, Entisols, and Aridisols. The <br />presence of these three orders is characteristic of the soils found in steep, semi -arid <br />regions of Northwestern Colorado. These orders represent soils that grade from recently <br />developed soils with minimum horizon development to more developed soils with well- <br />developed diagnostic horizons. Specific soil types within these orders occur on <br />predominantly three types of parent material -land form combinations, namely: 1) upper <br />side slopes, ridges, and swales of sandstone residuum; 2) toe slopes, side slopes, rounded <br />ridge tops of shale residuum and colluvium; and 3) toe slopes, side slopes, ridges, and <br />escarpments of sandstone and shale. Among the 22 soil types occurring within the permit <br />area, major topsoil salvage limitations include clay textures, high coarse fragment content, <br />steep slopes, shallow bedrock, salinity, and alkalinity. <br />SP stripped topsoil in single lifts once the woody vegetation which would interfere with <br />handling of the topsoil has been removed, pursuant to 4.06.2(1). As an optional approach, <br />SP obtained approval to use a roto -clear machine that reduces large woody vegetation to <br />chips, so that the vegetative material could be incorporated with the topsoil during salvage <br />operations. This technique has been successfully employed at other surface mines in the <br />region, and was used in the aspen habitat within the Wolf Creek/Sage Creek mining block <br />in 2004. Topsoil was redistributed immediately on regraded areas when possible or was <br />stockpiled in designated storage areas pursuant to 4.06.1(2). The amount stockpiled <br />depended on pit advance, season of the year, and reclamation activities taking place at the <br />time of salvage. Stockpiled topsoil was placed in stable areas and protected from wind <br />and water erosion by planting of a quick -growing vegetative cover. Single lift stripping <br />mixes different soil horizons and thereby dilutes heavy clay concentrations encountered <br />in various subsoils. Although soil survey information and soil handling plans contained <br />in the PR -1 application were detailed and comprehensive, several issues of concern were <br />raised during the adequacy review. <br />V. Sealing of Drilled Holes and Underground Openings <br />All exploration, drill or boreholes, wells, or other underground openings except those <br />used solely for surface blasting and the water supply well located in TSN, R8 8W SW '/4 <br />NW'/4 Section 22 will be plugged or sealed to prevent acid or toxic drainage from entering <br />the groundwater, minimize disturbance to the prevailing hydrologic balance, and ensure <br />safety. Details of the sealing plan are located in Tab 18, Volume 12 of the permit <br />application package. No variance from regulatory requirements regarding sealing has <br />been requested or proposed for approval, and no such specific findings apply. The <br />Division requires that each hole, well or underground opening be capped, sealed, <br />backfilled or otherwise properly managed (4.07.3). <br />VL Use of Explosives <br />Explosives were used to fragment overburden and exposed coal at the Seneca II -W Mine. <br />SP typically used ammonium nitrate and fuel oil (ANFO) for this purpose, primed with <br />cast primers and detonated with detonating cord. A certified blaster was in charge of all <br />blasting operations to ensure compliance with State and Federal laws. Additional <br />27 <br />