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~~~..$~"r ... INSPECTION REPORT ~ !r. ~~ ,•o ,. _ '= ~• ` ., Site: National King Coal Mine, Hesperus, Colorado ~ `•., ~, lZ?/~~, :,, 4-°., Inspected By: Don R. May, P.E., Project Engineer ,, ~°~~... Ins ection Date: Quarterl Ins ect3on, Janua 16, 2000 ~~~~''y3'~''"''~ ~` ,, .,.... Ponds: The east and west sedimentation ponds and their embankments appear in good condition. The west pond is shown in photograph 1 and the east in photo 2. The east pond has been cleaned out since the last inspection. Due to ice I cannot determine if the west pond has been cleaned. If not, it should be cleaned as stated in the last inspection report. As mentioned in previous reports, the inlet elevation of the pipe connecting the two ponds should be checked to assure it is below the low level outlet and spillway elevations. Drainage Ditches: The east side ditch which runs from just behind the office towards the waste rock pile should be cleaned and reshaped, photograph 3. This ditch is suppose to intercept clear water off the hillside and route it behind the office and offsite, photograph 3. Other ditches in and around the yard are in good condition, photograph 4. Photograph 5 shows an inlet grate, below the conveyor belt, that is nearly completely blocked with ice and debris. This same grate was identified last inspection as having holes in it large enough to pass rock which could accumulate in the pipe. The ditches on both sides of the waste pile face continue to slowly erode (especially the north side, photo 6). These ditches need to be armored as stated in the plans. Care should be taken when dumping waste rock to keep a uniform channel shape along the length of the ditch on the south side of the pile top so that runoff will flow toward the front of the pile as designed. All drainage features, with the exceptions stated above, have been constructed and are operating as stated in the drainage plan submitted to the Division of Minerals and Geology. Coal Waste Pile:: The face of the waste rock pile appears stable with no changes since the last inspection. The top of the pile was designed to slope from the north to the south. It is not visually apparent that this is the case. There is a large bean that will keep any runoff from the top of the pile from entering the clean water ditch on the north side. However, future waste material should be placed to assure the proper slope on the top of the pile. Recently placed fill on top of the pile should be graded and compacted to conform to the reGamation plan requirements. The end of the existing underdrain should be located and plans for the construction of the structure to connect it with the extension should be made as per the reclamation plan. Density tests on the fill should be pertormed to assure compliance with the plan specifications. To the best of my knowledge this has not been done since redesign and construction of the reconfigured pile. Except for the items mentioned above the fill on the waste pile has been constructed as specified in the design approved by the Division of Minerals and Geology.