2013-04-09_REVISION - M1977215 (4)

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Proper reclamation procedures should call for covering tailings with sufficient soil material suitable for plant growth. The material will most likely be obtained from the present soils and the usable portions of their C horizons as is necessary. This will, of course, involve the disturbance, transportation, and respreading of the soils, with inevitable mixing and alteration. For most shallow, immature soils encountered in wooded tracts of these areas, an average of about six inches is considered usable for topdressing, and even this will be of poor quality. Materials will range from sandy loam to light clay loam in texture, have very weak natural soil structure, and range from about neutral to moderately alkaline. They can be worked into good seedbeds, but they will retain their original poor and unse.abte structure. Consequently, they will easily disperse when wet, form crusts when dry and be moderately susceptible to wind and water erosion. Their total water holding capacity should range from moderately low to medium. If the surface 16 inches of the well drained, fine textured, immature soils in areas C and B were mixed for topdressing, the texture of the material would not change appreciably from that of the original soil - a sandy clay to clay loam. The good granular structure of the A horizon would not be destroyed but would become part of the matrix between coarser materials. Shearing stress during disturbance may promote better aggregation than exists in the original soil. Although artifcially created, these aggregates would still promote aeration, water movement, and unimpeded roof growth. Such a seedbed mixture should have a high moisture holding capacity, a moderately high wilting point. Initial infiltration should be moderate, but permeability would become moderately slow as the soil mass became wet. Packing by heavy machinery will cause a pressure pan to form, and severe puddling may occur if the soil is handled wet. Because of fine texture and poor structural stability, the range of soil moisture over which this soil can he handled and still retain optimum physical properties is relatively narrow. Soil fertility is moderate in this group but some supplemental fertilization will be necessary to insure vigorous seedling growth. Small parcels of moderately deep, medium textured, well developed soils occur on lower sideslopes and more stable positions in Units E and F. All exhibit well developed B2T horizons containing more clay than the A or C horizons. A topsoil mixture should have a loam to sandy clay loam texture. Such a mix could be easily worked into a good seedbed. Natural soil structure in these soils is good and moderately stable. The subangular blocky peds will provide some needed protection from wind erosion in the earlier stages of the revegetation process.