2009-08-21_GENERAL DOCUMENTS - C1981008

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Soils There are three major soils types at the original New Horizon Mine 2 area (see Baseline Soils Map 2.04.9-1 of the permit application): Progresso-Bond Complex, 2 to 15 percent slopes; Barx sandy loam, 1 to 4 percent slopes; and Haplaquolls, 1 to 3 percent slope. The Progresso-Bond complex is comprised of 40 percent Progresso, 40 percent Bond, 10 percent Barx (see below), 5 percent Travesilla, and 5 percent Bowdish series soils. The Progresso series is classified as a fine-loamy, mixed, mesic, Ustollic Haplargid. The Bond series is a loamy, mixed, mesic Lithic Ustollic Haplargid. The main difference between these two is the distance to bedrock; Bond soils are shallow (17 to 19 inches to bedrock) while Progresso soils are fairly deep (36 inches to bedrock). This complex is found on gently to strongly sloping irrigated uplands over much of the New Horizon Mine 2 area. The soils are shallow to moderately deep, well-drained sandy loams formed in sandstone derived alluvium. Topsoil quality is good to an average depth of 2.1 r feet. In the original Mine 2 permit area, the Barx soil is found in the southeast corner, primarily within Mapping Unit D-70B. It is classified as a fine-loamy, mixed, mesic Ustollic Haplargid. It is a deep, well-drained sandy loam formed in sandstone derived alluvium. Part of this soil unit (about 15 acres) had initially been classified as prime farmland, but based on a letter of October 14, 1992 from the Soil Conservation Service (now NRCS), it was determined that the Barx soil unit within the permit area (as delineated at that time) was not prime farmland, and further, that there was no prime farmland within the permit area (as delineated at that time). The ephemeral drainages of the Mine 2 area contain three families of Haplaquoll soils; Lithic, Lithic/Typic, and Typic Haplaquolls. The loamy, mixed, mesic, Lithic Haplaquolls are found in the upper reaches of the swales in the area and are the shallowest of the three series (bedrock at 11 inches). Lithic/Typic Haplaquolls (coarse-loamy, mixed, mesic, moderately deep Typic Haplaquolls) are found in the mid to lower reaches of the swales and exhibit good quality soil to a depth of about 24 inches. The fine-loamy, mixed, mesic, deep Typic Haplaquolls are found in the lower reaches of the swales and along Calamity Draw. These soils have sandy loam and loam textures to a depth of about four feet with sandy clay loam below that. The soils were classified as Haplaquolls because of soil wetness. However, this diagnostic factor is artificially induced because of irrigation water. The soils were formed in the alluvium of the swales. Fair to good quality topsoil exists in the swale areas in thickness from 1.2 to over 4 feet. In association with Permit Revision No. 5, a new soil survey encompassing approximately 442 acres to the north and west of the previously approved New Horizon Mine 2 permit area was conducted. The Order 1 survey was conducted in 1998. Map unit designations differ from previous surveys due to recent changes in NRCS soil taxonomy. Map 2.04.9-1 (Certified 7/31/2008) delineates the soil mapping units associated with the various surveys. Dominant map units identified in the 1998 survey include Bowbac-Bowdish Complex, 0 to 3% slope, Darvey- Barx complex, 0 to 3% slope, and Monierco Fine Sandy Loam, 0 to 10% slope. The Bowbac- Bowdish and Darvey-Bari complex units are used primarily for irrigated hayland or pastureland. The Darvey-Bari complex (Mapping Unit 98E) dominates that portion of the expanded permit area located south of BB Road and west of 2700 road. Based on information provided by NRCS during 2007 and 2008, Mapping Unit 98E south of BB Road and west of 2700 Road has been 14