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III. COMMENTS -COMPLIANCE Below are comments on the inspection. The comments include discussion of observations made during the inspection. Comments also describe any enforcement actions taken during the inspection and the facts or evidence supporting the enforcement action. The coal waste disposal area vicinity had dried out considerably since the previous inspection. The sediment pond was dry. Collection and diversion ditches and culverts were (with the exception of CMP-3 addressed previously) in place and functional. Collection and diversion ditches, and SAE sediment controls at the mine site and loadout appeared to be properly maintained and functional. Backfill and Grading A-new hole had opened up above the same sealed portal where caving had occurred last year. The operator had tilled in the hole prior to the inspection. Additional grading of the repair area will be necessary when the soils dry: further, to blend the repaired area. into.the slope above,. and to establish positive drainage away from the location. Seeding will be necessary upon completion of grading work. There had been a small surficial slump on the outslope of the interim reclamation coal backfill, near the upper (eastern) end of the backfill. The slump was approximately 12 feet across, and had been recently regraded by the operator. When the material dries further, additional final grading with the hoe bucket will need to be accomplished, to break up clodded material, and leave a roughened surface for seeding. There were additional settling cracks apparent in the immediate vicinity of the slump on the coal bench _ outslope.. There also appears to have been renewed surficial,sloughing.of material from portions of the highwall/cut slope above the coal backfill, which had experienced. slumping many years previously. ._ . , Jim Stover, P.E, provided a certification for the mine portal backfill dated 11I29I01. Given the indications of potential instability described, reevaluation of the portal area backfill stability by a professional engineer is warranted. Please submit an initial P.E. inspectionlevaluation report addressing the Munger portal backfill stability by June 15, 2005, to include any recommended remedial measures. If. remedial measures are recommended, the work will need to be completed by: August 1.5, 2005..An amended Mine ra.. Portal Backfill Certification will need to be provided upon completion of recommended remedial measures. - Processing Waste The initial phase construction of the coal waste disposal area was completed in November 2004. Topsoil salvage and storage, foundational preparation and cover soil stockpiling, and construction of drainage and sediment control facilities were constructed and several truck loads of material were hauled from the sediment drying area at McClave Canyon Mine to the disposal area in late November/December. At present, the disposal site is an excavated pit, created by removal of the subsoil/alluvial material that was stockpiled for use as non-toxic cover during reclamation. The waste material has recently dried sufficiently to allow equipment access, and the dumped material has been graded across the base of the pit, since the previous inspection. The material will need to be compacted in individual lifts that do not exceed two foot thickness. P.E. certification of placement and compaction in compliance with permit and regulatory requirements is required. It was observed that a couple large slabs of sandstone had slid down into the excavated pit at the southeast corner, along with a single juniper tree. This apparently occurred during the original excavation work. The tree will need to be removed prior to placement of coal waste at that location. The sandstone slabs will need to be removed, if necessary to ensure proper placement, compaction, and stability. 4