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Unsuitable Spoil Mitigation Plan If one or more parameters fall within the unsuitable range at a given grid point, athree-part mitigation plan will be implemented. 1. The area around a suspect hole will be sampled on a closer spacing interval in order to better define the lateral extent and variability of the unsuitable material. 2. In those areas where specrfic geochemical or physical problems are encountered, the regraded spoil will be mechanically loosened and mixed by ripping, chiseling, or approved alternate forms of scarification, The major advantages of scarfication are related to the physical properties of the spoil. The topsoil and spoil are scarified to decrease compaction, increase aeration and water movement, and increase plant rooting depths. Increased water movement may, to some degree, allow more downward leaching of carbonates. Therefore, although the greatest benefits of scarrfying are related to the physical soil properties (density, porosity), a lesser geochemical benefit (increased rate of carbonate leaching due to increased water movement) may result. 3. If none of the above procedures satisfactorily mitigate a certain problem, the Division will be notified and recommended actions will then be implemented. WFC will maintain and periodically review the existing quality control program used_to evaluate overburden, interburden, and spoil handling activities at New Horizon Mina. WFC will maintain records of the sampling results for each logical reclamation unit. New Horizon 2 Compactibility and Fsodibility Determining the compaction potential of disturbed overburden is important to assess postmine spoil conditions including: hydraulic conductivity, revegetation success, landscape stability, and equipment trafficability. Generally, stability and/or compaction problems are related to soils high in shrink swell clays, soils with large proportions of sand and clay (sandy clay texture), and soils with approximately equal proportions of the sand, silt, and clay-size particle fractions. These three conditions are not highly desirable since a high shrink swell clay content in postmine landscapes causes poor stability and low permeability conditions, a sandy clay textured soil develops surface crusting problems, and an equal particle-size distribution causes excessive compaction which results in restricted water movement and root growth. The first two considerations listed above were among those used for establishing the grading system for texture. Unsuitable clay textures were identrfied within two thin lenses of the upper overburden in 2.05.4[2)[d)-4