2016-01-07_PERMIT FILE - C2010089A (18)

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error in the NRCS soils mapping had to do with their delineation of soils mapping unit 71, Nyswonger silty clay loam, 1 to 4 percent slopes being presence on this site. This soils mapping unit is reported to be a Prime Farmland soil if irrigated. As are carefully documented in the response to permit section 2.04.12, Prime Farmland Investigation, the NRCS mapping of this site is in error because the slopes found on this site do not correspond to the NRCS definitions and the soil pedon of this site clearly established that this soil mapping unit actually corresponds to the Pinon phase of NRCS soils mapping unit 77, Pinon - Progresso loams 3 to 12 percent slopes. Three of the NRCS soils mapping units are mapped as complexes, meaning that soils of differing characteristics are lumped together. These include soils mapping unit 77, Pinon - Progresso loams 3 to 12 percent slopes, 78 Pinon - Ustic Torriorthents Complex, 5 to 30 percent slopes, and 88 Rock Outcrop - Orthents Complex, 40 to 90 percent slopes. Given the information obtained from the backhoe soil pits, and the detailed topographic mapping available from this site, it was possible to separate out these individual soils mapping units. This information is presented on Map 2.04.9-2, New Horizon North Mine - Soils Map. Separation of the two phases of soils mapping unit 77, Pinon - Progresso loams, 3 to 12 percent slopes, was accomplished based on the major different that Pinon soils typically have bedrock at less than 20 inches, while the Progresso soils typically extend to a depth of upwards 40 inches. Similarity, the two phases of soils mapping 78 Pinon - Ustic Torriorthents Complex, 5 to 30 percent slopes and 88 Rock Outcrop - Orthents Complex as accomplished based upon the distinguishing high rock fragment content of the Ustic Torriorthents soils and exposed bedrock. The separation of the designated NRCS slope phases for the Pinon and Progresso soils, into their formal slope phases was readily accomplished using the detailed two foot contour interval topographic map prepared for this project. The final soil mapping unit boundaries based upon the published NRCS definitions are presented on Map 2.04.9-2, New Horizon North Mine - Soils Map. This formal order I level of soil survey retains the original NRCS soils names but uses a slightly different nomenclature, based totally on the NRCS soils descriptions to identify the soil types found on this site. TOPSOIL SUITABILITY Application of the Wyoming Department of Environmental Quality "Suitability Ratings for Soils as Sources of Topsoil Material resulted in all of the soil samples being rated as "good" with respect to soil reactivity, electrical conductivity, saturation percentage, sodium adsorption ratio, Selenium and Boron. Texturally, the samples were classified as corresponding to the "good" to "fair" suitability classes. With respect to Moist and Dry Consistence, most of the samples were found to correspond to the "good" to "fair" suitability classes. Section 2. 4.9 Page 30 Sept. 2015 (TR -11)