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Soils <br /> Soils prevalent within and adjacent to the mine plan area are typical of the soils found in cold, <br /> semiarid regions of the Western United States. The soils are generally moderately deep (20 to 40 <br /> inches) to shallow (10 to 20 inches) and have developed in weathered, interbedded fine sandstone, <br /> siltstone, and shale, and in local slope wash and colluvium. The majority of soil types found in the <br /> mine plan area comprise a minimum of six inches of suitable topsoil material. Supporting <br /> documentation is found in Tab 9 and associated appendices. <br /> Salvage depths vary from 6 to 64 inches, resulting in an overall average soil replacement depth of 1.3 <br /> feet(15.6 inches), over regraded areas of the original permit area. Average soil replacement <br /> thickness in the South Extension area is 1.1 feet (132 inches), with the exceptions of aspen <br /> establishment areas,where average replacement thickness is 4 feet, and upland shrub establishment <br /> areas topsoiled in 2006, where average replacement thickness is 0.6 feet (7.2 inches). <br /> Vegetation <br /> Vegetation in the vicinity of the mine is characterized by three vegetative types: <br /> 1. mixed brush <br /> 2. sagebrush grassland <br /> 3. and aspen. <br /> Aspen forest is the dominant vegetation type within the Wolf Creek/Sage Creek mine block <br /> disturbance area. Because of livestock grazing, shrubs have increased in density while fortis and <br /> grasses have decreased. <br /> Fish and Wildlife <br /> Numerous wildlife species inhabit the general area of the mine site. The predominant big game <br /> species are Cervus elaphus (elk) and Odocoileus hemionus (mule deer). Antilocapra americana <br /> (Pronghorn antelope) frequent the vicinity of the tie-across haul road. Common raptors include <br /> Aquila chrysaetos(golden eagle), Buteo jamaicensis(red tail hawk), Bubo virginianus (great horned <br /> owl), Circus cyaneus(marsh hawk), and Falco sparverius(American kestrel). Various species of <br /> rodents, small mammals and water fowl inhabit the site. <br /> Cultural and Historic Resources <br /> The applicant conducted a number of site-specific literature searches and archeological surveys of the <br /> permit area between 1979 and 1990. SPL completed archaeological surveys of all currently permitted <br /> and proposed areas associated with mining activities. The cultural resource inventories identified 10 <br /> sites and 5 isolated finds. Of these, only 2 were considered significant: one rock art site with <br /> adjacent fire-rock and one potential large camp site. Appropriate mitigation measures were <br /> implemented for the rock art/fire-rock sites. <br /> Operation and Reclamation Plans <br /> The operation plan is addressed in detail in Volume 7, Tab 12. The permit application provides <br /> detailed information on mining and reclamation operations,transportation routes, and hydrologic <br /> controls for the mine. Mining was completed and coal extraction at Seneca IIW ceased in early <br /> January 2006. <br /> The Seneca IIW Mine is a surface mine operation. The mine was a dip-slope, area strip mine <br /> utilizing conventional dragline mining methods and included auger mining in certain locations. The <br /> mine area permit boundary includes three separate areas (North Block, South Block, and South <br /> Extension) with associated facilities. The North and South blocks comprise the original mine <br /> permit area, while the South Extension was a permit area expansion approved with PR2. The final <br /> areas mined were the Wolf Creek and Sage Creek seams in the South Extension Area. <br /> Within the original permit area,Mine Pits A, B, C, and D were oriented perpendicular to the crop <br /> Page 8 of 37 <br />