2010-05-07_PERMIT FILE - C2009087 (8)

Home Browse Search

RULE 2 - PERMITS 2.04.9 Soils Resource Information • This section of the permit application describes soil resource occurrence and characteristics in the PSCM permit disturbance area and adjacent areas as a basis for understanding site - specific land use, vegetation, habitat conditions, evaluation of potential mining - related impacts, and development of plans for soil recovery and replacement as part of the comprehensive site reclamation plan. Information presented in this section is based on two sources: 1) general soils mapping and characterization survey of Routt County conducted by the US. Department of Agriculture Natural Resources Conservation Service (NRCS, 2008); and 2) the Soil Resource Survey of the Sage Creek Coal Mine Routt County, Colorado ( Nyenhuis, 2009) presented as Exhibit 2.04.9 -E1, Soils Information. The Natural Resources Conservation Service (NRCS) mapping and soils descriptions were used to evaluate the PSCM permit area. The Order I Soil Resource Survey conducted by Mr. Nyenhuis was used to evaluate the proposed surface disturbance area. The soils study area for this second survey was approximately 12,075 acres. However, at the time of the survey, the potential surface - affected areas consisted of approximately 240 acres as opposed to the current area of approximately 391 acres. Thus, an area of approximately 151 acres within the eastern surface disturbance area boundary was not mapped as part of the Order I survey. However, all of this proposed surface disturbance area that is not mapped under Nyenhuis's 2009 Order I Survey is comprised of Seneca II Mine reclaimed pit overburden and redistributed topsoil. The unmapped area is bordered by soil mapped as REC or Reclaimed Land. Soils Information • Soils development and occurrence in the PSCM permit and adjacent areas reflects the dominant sedimentary geology of the area, the relatively rugged topography, and semi -arid climate. Based on the USDA NRCS Soil Survey of the Routt Area, Parts of Rio Blanco and Routt Counties, Colorado http:H websoilsurvey .nres.usda.gov /app[WebSoilSurvey the soils generally consist of shallow to moderately deep, moderately well drained and well drained productive Mollisols. Much of the area also consists of Vertisols (clay soils) and recently reclaimed soils mapped as poorly developed Entisols. The dominant soils within the PSCM permit boundary, as described by the USDA -NRCS, consist of moderately deep soil formed in residuum and colluvium derived from sandstone. These soils have moderately deep to deep A and B horizons extending as much as 24 inches below ground surface or more. However, these soils are interspersed throughout the area with very shallow soils on fractured sandstone and shale. Areas of deeper alluvial soils are present in the less steeply sloping and wider drainages. Soil textures vary widely from clay to sandy loam textures depending on the local parent materials with clay being the prominent soil texture in the areas not previously disturbed in the proposed PSCM disturbance area. General Soils Mapping USDA -NRCS mapping within the PSCM permit area and descriptions of individual soil map units are contained in the soil survey report on -line. The following principal soil mapping units were • each present in over 400 acres of the area. The total acreage of the principal soil map units covers over 77 percent of the area. PSCM Permit App. 2.04 -119 Revision 12/17/09