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III IIIIIIIIIIIIIIII INSPECTION REPORT 999 RECEIVED Site: National King Coal Mine, Hesperus, Colorado JUN 2 3 1897 Inspected By: Don R. May, P.E., Project Engineer r)lvleion or i~mera~s t~ Geology Inspection Date: Quarterly Inspection, June 6, 1997 Ponds: The east and west sedimentation ponds and their embankments appear in good condition. The west pond is shown in photograph 1. Sediment deposition can be seen in this photo and is monitored by measurements on the staff gage. Drainage Ditches: The east side and west side drainage channels appear in good general condition. Photograph 2 shows the east side ciearwater diversion ditch adjacent to the waste rock pile. Photograph 3 shows the same ditch behind the office. The drainage ditch at the toe of the waste pile is shown in photograph 4. This ditch and the one on top of the pile are in good condition. The yard is dry and all drainage features appear to be operating properly. Previous inspection reports discussed a problem where runoff from the lower yard area flowed along, and in, the access road, between the ponds and out into the adjacent pasture. It was recommended that this be corrected with aditch/pipe diversion structure in the road to intercept the water and divert it into this east pond. Photograph 5 shows recent graci~,^ modifications to the road which have created a dip section to attempt to achieve this diversion into the east pond. The photo is looking down the road into the dip section and east pond. All other ditches and structures were inspected and appear in good operating condition. All drainage features have been constructed and are operating as stated in the drainage ~ an submitted to the Division of Minerals and Geology. Coal Waste Pile: There are no visible signs of structural instability on the waste pile. Photographs 4 and 6 shows the front face of the waste pile. The slope of the face appears to exceed the design slope of 3:1 (horz:vert). This should be confirmed and adjustments ~~ jade to the face as needed to assure the design slope is met. The highwall and other slopes at the site appear stable. As reported last quarter, it appears that waste material is being generated in larger amounts that initially expected and hence the waste pile is approaching the final design volume prematurely. This concern is being address by the redesign of the waste pile which is currently being performed. 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.