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~... ,~~ .. `., '~' INSPECTION REPORT ' ~'~' " Site: National King Coal Mine, Hesperus, Colorado A ~ ` ~~ ~~ ~G Inspected By: Don R. May, P.E., Project Engineer .~;~'•. / . ~-.., Inspection Date: Quarterly Inspection, October 8, 1999 ••~;;.~~i,;;~r:,._ ` •~: ~.,,_ Ponds: The east and west sedimentation ponds and their embankments appear in good condition. The west pond is shown in photograph 1. 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. The west pond staff gage reads about 3.5 feet where as last inspection it read 2 feet. As seen, water in the pond account for some of the depth but sedimentation has occurred and should be removed. The east pond is in good condition. Drainage Ditches: Photograph 2 shows the east side ditch below the office near the old tni~~~ s:.~ciures. s seer., hca:~y s~,ri:mer rains has resu!'~d i~ se~;^•~^tation in portions of this ditch and should be removed. This is also the case for the small ditch which runs from just behind the office towards the waste rock pile, photograph 3. Other ditches in and around the yard are in good condition. Photograph 4 shows a grate with holes in it over the inlet to a drainage pipe in the yard. Rocks large enough to cause blockage could accumulate in the pipe. The ditches on both sides of the waste pile face continue to slowly erode (especially the north side). These ditches need to be armored as stated in the plans. The inlet to the pile on the north side should have a trashrack. 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, photograph 5, has some vegetative cover and appears stable. The top of the pile, photograph 6, was designed to slope from the north to the south. It is not visually apparent that this is the case. A large berm 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 reclamation plan requirements. Density tests on the fill should be performed to assure compliance with the plan specifications. 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. 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.