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I ~ 2.04.9 -SOIL RESOURCE INFORMATION Soil Resource Inventory The U.S. Department of Agriculture Soil Survey of La Plata County, Colorado (1988) identifies four soil series within three map units in the area of the project that is proposed for surface disturbance. The distribution of the soil map units is depicted on map King II-006. Data sheets for soil sample locations and analysis summaries are contained in Appendix 6. Umbarg soils are found within the level colluvial deposits between the bordering sideslopes of the drainage basins. These are fine-loamy, mixed mesic Cumulic Haplustolls. These soils typically form in alluvium on fans and upland valley bottoms. They are deep and moderately well drained. The presence of this soil series was confirmed by sampling at three locations within the proposed area of disturbance (sample points U1, U2, and U3). Soil suitable for plant growth and revegetation was identified to an average depth of 25.3 inches. The Lazear-Rock Outcrop Complex was mapped and confirmed on the northeast, south, and southwest facing drainage sideslopes within the project area. This map unit comprises the Lazear series and exposed rock outcrops (in this area, sandstone and shales). The Lazear series is described as a loamy, mixed (calcareous), mesic Lithic Ustic Torriorthent. This series is shallow and well-drained, formed in residuum and alluvium derived from sandstone. This soil map unit (and the Lazear series) was confirmed at two sample sites on either side of the drainage basin in the proposed location of the portals and surface facilities (sample points LRO1 and LRO2). Soil test pits revealed variable depths of plant growth medium ranging from five to 28 inches. Salvage within this soil type will be dependent on the near surface proximity of sandstone outcrops. The third soil map unit identified within the potential surface disturbance area is the Archuleta-Sanchez Complex located on the northwest facing sideslope along the east drainage basin arm. The complex is comprised of 45 percent Archuleta loam and 30 percent Sanchez very stony sandy clay loam. Remaining constituents are clays, loamy, and rock. The single sample point (AS1) within this complex revealed the presence of the Sanchez series. This soil is aloamy-skeletal, mixed Lithic Eutroboralf. These soils are shallow, well-drained and formed in w d/!J/~ /P/IVq/O/O/O/O/N//1/b% 6/O/.O/s9//9/Y/®/4/tl/N/N/N/®/O% /R/6~/M/4/O/fl/4% /9/®/a/O/Gl/4/%/L+/O/N/!l/G/®/N/if~0/O/lO/®////F/{~~O/ ~ /N Y/(1/M/Y/v+/~ National King Coal, LLC King II Mine Section 2.04.9 Page 1 October, 2005