2009-10-13_PERMIT FILE - C1991078A (3)

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2.05.3(6) • It is probable that this suspect layer of gray shale will be visually identifiable which will provide the scraper/dozer operators the ability to consciously blend the material during normal operations. If the material is not visu- ally identifiable then it will be identified by horizon location and blended during the normal overburden/interburden handling operation. It is believed that this zone of gray shale is present throughout the mining area although some areas may be "hotter" that others. Where blending or normal burial are ineffective, the suitable plant growth horizon will be selectively handled as a topdressing material to ensure that all unsuitable regraded spoil is covered. In these situations, unsuitable spoil will be top- dressed with a minimum of four feet of suitable material which includes replaced topsoil thickness. The upper three feet of regraded overburden will be sampled prior to topsoil replacement. Two representative sam- ples, each representing an eighteen inch increment swill be collected on a 300-foot grid center. The surface spoil will be visually inspected between grid points. If a significant change in spoil characteristics is observed between sample points then additional sample points will be located. Regraded overburden samples will be analyzed for the following parameters to deter- mine suitability for subsoil: pH, sodium absorption ratio, acid- . base potential, iron, particle size and electrical conductivity. If any of the analysis indicate that the overburden is unsuitable for subsoil then additional samples will be taken to isolate the unsuitable area. Mitigation techniques will include either removal and replacement of the unsuitable subsoil or incorporation of adequate quantities of agricultural grade lime- stone. Additional discussion of overburden backfilling and grading is presented in Section 2.05.4(2). • 2-05-12i July 1991