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<br />illustrated in the soils map provided in Figure I-1. The irregular-shaped polygons <br />outlined in black represent the 5-year mining panels, the areas where solution mining <br />will occur. <br />The Redcreek-Rentsac complex, Rentsac, and Torriorthents-Rock outcrop complex units <br />occur on ridges and mountainsides with slopes ranging from 5 to 90 percent. These <br />units are typically channery loamy and sandy loams with moderate to moderately rapid <br />permeability and very low available water capacity for revegetation. The water erosion <br />hazard is moderate to very high, generally increasing with increasing slope steepness, <br />and the wind erosion hazard is slight to high (SCS 1982). Topsoil' depths of the <br />Redcreek and Rentsac soils generally range from 9 to 11 inches. The surface layer of <br />Torriorthents is commonly about 3 inches deep, with an additional 13 inches of <br />underlying material. Limitations to consider in reclamation of these soils include <br />shallow rooting depths, a high percentage of coarse fragments, and steep slopes. These <br />soils are considered fragile according to the criteria described above. These soils <br />comprise 3,170 acres (78 percent) at the Piceance Site. Of these, approximately 470 acres <br />of Rentsac and Torriorthents soils would be disturbed in the process of developing the <br />solution mining well field over the 30-year proposed mine life az~d would subsequently <br />be reclaimed on a revolving basis as described above. An additional approximately 35 <br />acres of these soils would be disturbed for project facilities. Temporary construction <br />disturbance would affect approximately 213 acres of these soils. <br />Yamac soils are located on rolling uplands in the western and northwestern portions of <br />the Piceance Site. These soils are deep, well-drained loamy, with moderate permeability <br />and moderate to high available water capacity. Slopes range from 2 to 15 percent. <br />Water erosion hazard is slight to moderate, and wind erosion hazard is slight (SCS <br />1982). Yamac loam soils have no limitations relative to soil salvage and reclamation <br />potential and could be a good source of materials Eor reclamation. Typical topsoil <br />depths are 22 inches. This soil unit comprises 696 acres (17 percent) at the Piceance Site. <br />Only 10 acres of Yamac soils would be disturbed for development of the solution <br />mining well field, and 31 acres would be disturbed for project facilities. Temporary <br />construction disturbance would affect approximately 5 acres of Yamac soils. <br />Barcus channery loamy sands are located near the Piceance Creek valley floor. This <br />series consists of deep, somewhat excessively drained soils, with rapid permeability and <br />low available water capacity. Water erosion hazard is moderate, and there is no wind <br />erosion hazard. Limitations for Barcus sands include a high proportion of sand just <br />below the surface layer and low available water capacity for revegetation (SCS 1982). <br />Furthermore, typical topsoils are only 6 inches deep, and subsoils are lacking. <br />Although this soil unit comprises 180 acres (4 percent) at the Piceance Site, only <br />The term topsoil, as used here, refers to the upper part of the soil (the A soil horizons, as <br />described by the SCS), which is the most favorable material for plant growth. The term subsoil, as used <br />here, refers to the B soil horizons, which may also serve as suitable growth mediums for revegetation. <br />Substrates include the C soil horizons, which aze not considered suitable growth mediums. <br />I-3 <br />