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Lorencito Canyon Mint - Soitr Technical Report <br />• Cooperative Soil Survey. Included is the thickness and physical description (color, texture, <br />structure, root abundance and size, dry and wet consistence, and plasticity) of each horizon as well <br />as the nature of the boundaries between horizons. In addition to profile characteristics, other <br />relevant landscape characteristics were also recorded including location, elevation, physiographic <br />position, slope, aspect, parent material, erosion, vegetation type and cover, and ground cover by <br />gravel and cobbles. For each profile, information was recorded on USDA Forest Service Form <br />13-2500-4 (Appendix S-2). <br />Soil samples from each identified horizon were collected from 14 of the pits and submitted to a <br />laboratory for chemical analyses. The parameters analyzed included four required by MLRB: <br />pH, texture, electrical conductivity, and sodium adsorption ratio. Other parameters analyzed were <br />saturation percentage, boron, selenium, and organic matter. <br />A narrative description of the soil survey results has been prepared that describes the <br />characteristics of the soil mapping units (Section 3). These descriptions surrunarize information <br />from the NRCS as well as the field and laboratory investigations of soils for the Lorencito Canyon <br />Mine. A soils map of the permit area (Map 2.04.9-1) has been prepared which depicts mapping <br />unit polygons, pit/profile locations, and a legend. <br />This soils information has been used to provide input to the responses to the reclamation section <br />• of the MLRB requirements. These data enable determination of the quantity and quality of soil <br />available for reclamation. <br />SECTION 3 -RESULTS AND DISCUSSION <br />Soil Mapping Units <br />The permit area is characterized by rugged mountain terrain which has developed in relatively <br />horizontal sedimentary bedrock. Shallow to deep residual soils have developed in the gently to <br />very steeply sloping upland areas. The uplands have been dissected by a dendritic pattern of <br />streams and minor drainages. Deep alluvial soils have developed in the two relatively broad <br />stream valleys within the permit area (Lorencito and Cow creeks). <br />Seven soil mapping units have been identified by the NRCS within the permit disturbance areas. <br />A brief description of each unit follows. More detailed information sheets for both the soil <br />mapping units and soil series are found in Appendix S-1. <br />Shawa Loam, 5 to 15 percent slopes (map symbol CeD) 8 <br />This is a deep soil which has developed in alluvium in the valleys of Lorencito and Cow creeks. <br />It is found at elevations of 6200 to 7800 feet in grassland communities. This is a well drained soil <br />soils.d76/December 1}, 1996 2 <br />