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~~ III IIIIII~IIIIII III INSPECTION REPORT Site: National King Coal Mine, Hesperus, Colorado Inspected By: Don R. May, P.E., Project Engineer Inspection Date: Quarterly Inspection, July 4, 1999 .~ I `~7v rte. ./ J~I ~J l,~ :~:: So; •.......••NV~~~•' ~w: ' ANAL E_.S~' 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. As seen some sedimentation has occurred and should be cleaned out this summer. The west pond staff gage reads atwut 2 feet. The east pond is in good condition. Drainacae Ditches: The east side (photograph 2 looking upstream behind office) and west side drainage channels appear in good general condition as does the drainage system in the mine yard. The entrance to the west side drain is partially blocked and should be cleaned, photograph 3. Ditches and other drainage features on the hillside behind the shop and are in good shape. Photograph 4 shows the ditch on the north side of the waste pile face looking down the slope. Due to the rocky nature of the material the channel has partially armored itself. Erosion has been minimal and does not pose any immediate threat. However, in the long run, the ditches (both sides of the pile) need to be armored as stated in the plans. The inlet to the pile on the north side should have a trashrack. The ditch on the south side of the top of the waste pile has been reshaped since the last inspection and is much better. Care should be taken when dumping waste rock to keep a uniform channel shape along the length of this ditch 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 Pife: As seen in photograph 5 the face of the waste rock pile is forming a nice vegetative cover. This will help mitigate adverse effects of the rather extensive rill formation that has occurred on the face. 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. A large berm, photograph 6, 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.