_GENERAL DOCUMENTS - C1981017 (249)

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permit contained little information regarding final topography of the pile, so grading requirements were created to meet the requirements of the area. Virtually no information regarding the Old Refuse Pile was available in the permit, excepting seed varieties and topsoil depth. Grading was accomplished as needed. Drainages will need to be constructed after vegetation is established. A discussion of the rationale for field changes made at each project follows. MINE 3 1) A concrete slab was left in place on a slope above the intermediate coal transfer area, because it appeared that excavation of the hillslope to remove the slab would have lead to creation of an oversteepened slope. 2) Silt fences below the construction area were allowed to be erected after bench excavation, rather than prior to excavation, when it became apparent that rock falling from the bench would destroy the fence very rapidly. 3) The amount of hay to be incorporated into the bench prior to seeding was reduced from 5 tons per acre to 2 tons or less due to the shallow depth of dirt, which was underlain by shale, sandstone and coal. It did not appear that the depth of dirt was sufficient to incorporate this amount of hay. 4) Slopes flatter than 3H:1V were allowed to be hydro seeded and mulched because the soil on the dirt was extremely rocky. In many areas, coarse rock was predominant close to the surface. It did not appear that a drill would penetrate in many areas, possibly leaving interstitial areas barren of seed. It was felt that hydro seeding would provide better coverage of the area. The contractor paid for the cost of extra seed needed. 5) A large cavity appeared in the southern portion of the highwall backfill well after backfilling operations were completed. It is speculated that this probably occurred due to failure of a block wall within one of the entries. The contractor was paid additional monies to fill the hole. 6) Surface containment furrows were constructed in a 'V' shape, rather than as a trapezoid, in order to simplify the construction process. 7) Only about one third (estimated 275 feet) of the north facing outslope were hydro seeded, rather than the entire slope. This was done for two reasons: the total amount of acreage estimated to be revegetated had already been slightly exceeded; it was becoming apparent that hydro seeding without additional treatment of the steep slope may have limited success. Additional seeding did not 8