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22 <br /> An erosion K and I factor was computed roughly from the guidelines of <br /> the universal soil erosion equation and nonographs provided by W.H. <br /> Wischmeier (1971) of USDA-ARS Research Laboratories, of Purdue Univer- <br /> sity. Since the very fine sand fraction was not determined, these K <br /> values are only approximate. The I value is taken from SCS tables <br /> applicable to soils of the Great Plains. Both moderate wind and water <br /> erosion susceptibility are indicated. <br /> The topsoil quality ratings are G = good, F = fair, and P = poor. The <br /> limiting factors are depth to shale or sandstone, presence of shale and <br /> sandstone fragments in the lower (C) horizons, increasing concentra- <br /> tions of CaCO3 with depth, consistence and texture of lower horizons <br /> and the steepness of slope affecting topsoil stockpiling operations. <br /> In Table 4 a total of 179+ acre feet of topsoil was computed with 87+ <br /> acre feet being of good to fair quality and the rest fair to poor or <br /> poor. With adjusted depths of cut(Table 2)shows 95 acre feet of usable <br /> fair to good quality material. <br /> Estimated Engineering Properies <br /> Table 5 summarizes fron the laboratory and field data a number of <br /> qualities commonly used in engineering and construction work. Particle <br /> size distribution is based on the lab data and on the assumption that <br /> a certain percent of very fine sand is in the sand fraction. Guide <br /> sheet 2, page 11, and Chart 1 A, page 73, of the USDA SCS Soil Survey <br /> Manual were used. Comparisons were made from Guide Sheet 15, page 72 <br /> of the Manual for USDA showing Unified and AASHO and USDA textural <br /> grade classifications. The principal texture was SCL (USDA) SC <br /> (Unified) and A-6 (AASHO) with 20-30% clay, 10-20% silt and 50-60% <br /> sand. <br /> The soils are moderately plastic, have moderate to moderately rapid <br /> permeability and available water capacity of .14-.18 inches per inch <br /> in the sandy clay loams and .11-.13 inch per inch in the sandy loams. <br /> They have moderate to low shrink-swell characteristics and fair to <br /> good compaction qualities. <br />