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According to Mr. Lewicki's geologic description, "significant scraping with a knife is needed to break out sizable amounts of the fines" indicating that the material may fall under an R3 rock classification. If this is the case, the applicant may need to concentrate on evaluating adverse fracture orientations, which would include conducting a field fracture mapping program to evaluate azeas where natural fractures may be problematic. The applicant did not address fracture orientations in the topsoil stockpile azea so, in my opinion, the applicant did not comply with Rule 6.5(1) since a complete geotechnical evaluation of all geologic hazazds was not submitted. However, it seems to me that DMG requirements could get awful complicated to ensure that the temnorazy highwalls aze stable during mining operations. These highwalls are going to be backfilled in order to create the final slope (which is proposed to be 3:1). If a portion, or all, of the highwall fails, the worst thing that would happen is the topsoil would probably be lost or mixed in with other materials and, therefore, unusable as a growth medium. To resolve the problem, the applicant could import, or salvage, sufficient topsoil material to provide the approved thickness of topsoil that the applicant committed to and include sufficient funds in the financial warranty to import the material. I would like to recommend that the applicant choose between two options; 1) conduct a fracture mapping program of the topsoil stockpile area to determine if there are adverse fracture orientations that could cause the highwall to fail prior to being backfilled (submit a revised mining plan if there is a high probability that the fracture orientations will cause a failure of the highwall), or 2) in addition to current proposed commitments (20 foot setback, conducting quarterly inspections of the highwall, etc.), the applicant shall commit to importing sufficient topsoil to complete reclamation and shall commit to provide sufficient funds in the financial warranty to import an amount of topsoil sufficient to provide the required layer of growth medium over a phased disturbed area. cc: Harry Posey (e-mail)