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9-29 <br />4.4.4.3 Suitability as a Source Material for Reclamation <br />of Disturbed Lands <br />• Each horizon of each sampled pedon is evaluated by the suitability <br />criteria (Table 4.4-35) for use as topsoil in Table 4.4-55. The <br />evaluation is based on the soil chemical and physical data, field <br />descriptions of coarse fragments, calculations of K factors <br />(Wischmeier and Smith 1978) and wind erodibility groups (USDA - <br />SCS 1978). <br />The topsoil suitabilities of the soils within the permit area <br />range from good to poor. The criteria of SAR, salinity, and soil <br />reaction were given primary importance in the rating. Available <br />water-holding capacity, water erodibility factor, wind erodibility <br />group, texture, and coarse fragments are considered less important <br />because soil amendments and handling procedures can improve these <br />factors. These factors were given secondary importance and some <br />soils are, for example, rated good-fair in the cases where the <br />primary factors are good and the secondary factors are fair. <br />• 4.4.4.4 Depth of Suitable Topsoil Material <br />A recommended depth of salvage for each map unit is given in <br />Table 4.4-6S. The recommended depth of salvage was empirically <br />determined using the evaluations made in Table 4.4-55, field <br />observations, and professional experience with the soils occurr- <br />ing at Munger and McClane Canyon Mines. Also given in Table 4.4-65 <br />are the principal restrictive features of the topsoil recommended <br />for salvage. These features are listed because they are important <br />to handling and reclamation planning. <br />Map units not recommended for salvage are comprised of soils rated <br />fair-poor or poor for alkalinity, sodicity, or salinity, or are <br />too thin, too sandy or stony. Map units on steep slopes (greater <br />than 15 percent) are also not recommended for salvage. <br />• <br />