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The chemical data for the soils is presented in Table 4-4-6 of the application. The pH range from 7.3 to 8.3 for these soils (Nihill and Rivra Variant). Electrical conductivity ranges from .4 to .9 mmhos/cm2 and sodium adsorption ratios are .2 to 5.6. Boron contents are .1 to .2 ppm. The analyses indicate that these soils are good sources for topsoil for use in reclamation of the mine. The operator salvaged the Nihill Loam soil to a depth of 12 inches and the Rivra Variant to a depth of 18 inches from the area of the proposed sediment pond This yielded a volume of 900 BCY of topsoil from the disturbed area. Part of this topsoil will be respread over one acre of the mine bench and the rest will be spread over the disturbed area of the sediment pond. These soils will be respread at a minimum depth of 4" which will be sufficient to achieve successful revegetation of the two areas. This determination is based on an evaluation of the salvaged material as well as the surficial material over which the topsoil will be respread. A portion of the bench and outslopes along the reclaimed road will not be topsoiled. These areas consist of fill which was used for grading the road and original ground. Prior to issuance of the initial permanent regulatory program permit, the applicant supplied analyses from grab samples of this material. Although these analyses indicated that the material is suitable for reclamation, it was insufficient for the determination of reclamation feasibility. A stipulation was subsequently attached to the initial permit which required the applicant to provide further analyses of the fill taken to a depth of 4 feet. The samples taken in response to the stipulation were composite samples taken to a depth of 4 feet. The analysis indicated slightly elevated SAR levels and an elevated salt level. None of these levels would create a problem during reclamation if proper cultural treatments are used. However, it was not evident whether one distinct layer was elevating these levels or whether the chemical characteristics were uniform throughout the four foot sampling depth. In general, the surface layer is the zone where any degradation of soil characteristics occurs on a mining operation through such things as deposition of coal, watering for dust suppression, and deposition of salts leached from nearby coal stockpiles. If the surface layer has been degraded by surface activities, this layer can easily be isolated during regrading. To determine whether the surface layer of the McClave Canyon Mine bench has been degraded by surface operations, and to determine whether high levels in the surface layer elevated the salt, SAR and pH levels of the four foot composite samples, the following stipulation is required: -21-