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i~~_ INSPECTION REPORT Site: National King Coal Mine, Hesperus, Colorado Inspected By: Don R. May, P.E., Project Engineer Inspection Date: Quarterly Inspection January, 2006 Ponds: The inlets, outlets and embankments of both ponds were inspected and appear in good condition. Photograph 1 shows the east pond. Both ponds are relatively clean of sediment and appear to have more than adequate storage volume. A staff gage marked with the pond bottom elevation would help the operator determine when and how much sediment removal is needed. Drainage Ditches: The drainage channels, on the north and south sides of the waste rock pile, appear in good general condition. Photograph 2 shows the north rock channel near the inlet. Some debris is present. The upper and lower yards are all in good shape. Especially within the year, care should be taken to keep the pipe drop inlets Gear of sediment. As seen in photo 3, the clear-water ditch behind the office trailer is in good shape. However downstream of the office, near the old tipple and the east pond, the channel is slightly widened and deepened to create a small sediment settling just above the discharge point from the mine grounds. This basin has been in existence for a long time and generally performs well. It appears that the berm on the downstream end is higher than the top of bank elevation upstream of the basin, photo 4. If this is the case water may back up and spill over the ditch bank and run into the east pond. The east pond was not sized to include flow from this ditch. These elevations should be checked and, if necessary, adjusted to assure proper performance. In addition the short section of ditch below the settling basin is poorly defined. A more definite channel should be created in this area. Except where noted, 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: As mentioned in previous inspection reports, over-steepening of the waste pile face at the toe of the slope still exists, photo 5. At this time there are no visible signs of structural instability on the waste pile but affix-for-this problems should be pursued. As described in the last report, the top of the waste pile has been reconstructed. It is very level with a good cross-slope. Photo 6 shows a channel that is forming in the swale along the south side of the top of the pile. The clear water ditch on the north side is in good shape. The top of the waste pile is in very good condition. 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.