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INSPECTION REPQRT Site: National King Coal Mine, Hesperus, Colorado Inspected By: Don R. May, P.E., Project Engineer Inspection Date: Quarterly Inspection, April 18, 2004 Ponds: The east and west sedimentation ponds and their embantvnents and outlets appear in good condition although the low flow exit pipe from the west pond is partially blocked as shown in photograph 1. The west pond is shown in photograph 2 with recent runoff water. The pond will need cleaning this summer. Drainage Ditches: The large, rock lined east side and west side drainage channels appear in good general condition. Some coal is getting into the top portion of this ditch, where it is adjacent to the access road, as shown in photograph 3. Care shceld be taken not to contaminate this dean water ditch. Drainage along the waste pile access road and other roads at the mina is performing according to the design plan. The upper and lower yards are all in good shape. Photograph 4 shows the area near the coal storage pile boking at the toe Of the waste pile. The yard drainage grates, pipes and ditches appeared dear and functioning. All other ditches and drainage structures were inspected and appear in good operating condition. There are no apparent drainage problems on the site. Except where noted, all drainage features have been constnxded and are operating as stated in the drainage plan submitted to the Division of Minerals and Geology. Coal Waste Pile: The coal storage in the upper yard has Deen completely depleted and is no longer impinging on the toe of the water pile slope. This qn be seen in photograph 4. Removal of coal that hid been placed on top of the Tower portion of the front face of the waste pile has resulted in over~teepening of the toe of the pile. This can be seen in photo 5. This photograph is of poor quality so l have indicated the effected area. To a {ergs extent, the tce of a slope controls the integrity of the entire slope. Care should be taken to assure that this area is regarded and compacted to desgn specifications. Secondly, this area should be vegetated in accordance with the approved mine plan. At this lima there are no visible signs of structural instability on the waste pile. The top of the waste pile, photograph 6, is in good condition but rough. The surface should be kept as smooth as possible to facilitate unimpeded flow of surface runoff to the dreinage ditch. This area should be graded with a 196-2% cross slope to a weli- fonned ditch on the east side. 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.