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INSPECTION REPORT :`o~ ~,cN r,. ' ~" ~ ~' ~ .. Site: National King Coal Mine, Hesperus, Colorado `~~. ,= Inspected By: Don R. May, P.E., Project Engineer %,cs,•,,..,..._ ~ .. Inspection Date: Quarterly Inspection, July 9, 2001 ~"•~~~~r;:;::• ~.: ' '~ Ponds: The east and west sedimentation ponds and their embankments and outlets appear in good condition. Routine cleaning is needed especially in the west pond. Drainage Ditches: The eastside and westside drainage channels appear in good general condition. Photograph 1 shows the armored ditch that runs down the north side of the waste pile and looks across the waste pile face down into the yard. Photograph 2 shows the ditch that runs down into the yard under the conveyor. These and all other ditches and structures were inspected and appear in good operating condition. Photograph 3 shows the road at the base of the high wall and photograph 4 shows the lower yard area below the scales. As seen the yard is in good condition. There are no apparent drainage problems on the site. All drainage features have been constructed and are operating as stated in the drainage plan submitted to the Division of Minerals and Geology. Coal Waste Pile: There are no visible signs of structural instability on the waste pile. Photograph 5 looks across the top of the pile toward the upstream drainage. New fill material is evident in the photo. The toe of the waste pile face has been cut to a steep angle to make more room for the coal truck while loading. This oversteepening of the face could result in instability. Photograph 6 shows this region. This area should be regraded the design slope of 3:1 and compacted to 90% proctor. It is important that the waste material be placed in lifts not to exceed 12" to 18" and that compaction results in the density stated in the design report. It is not possible to determine this by visual inspection and therefore the density should be periodically checked by measurement. It is recommended that the upstream end of the waste pile underdrain be located and marked. As the pile grow this task will become more difficulty. Except for the items mentioned above the waste pile has been constructed as stated in the reclamation plans submitted to the Division of Minerals and Geology.