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0 ~E INSPECTION REPORT Site: National King Coal Mine, Hesperus, Colorado ~ ~,, ~,~>~~i'~~ Inspected By: Don R. May, P.E., Project Engineer ''~.,~' ~ti,~~• `~~~~ Inspection Date: Quarter{y Inspection, June 28, 1994 °'"~''"' Ponds: The east and west sedimentation ponds are in good condition. There are no signs of erosion or excessive filling in of the ponds or the approach channels. Photograph #1 shows the West Pond, its front embankment and the spillway. The condition of the spillway and low flow outlet have not changed since the last inspection. See March report for recommendations. The East Pond is seen in photo #2. The pond and its embankments are in good condition. Drainaoe Ditches: As seen in photo #3 there are signs of some erosion around the outlet of the two 18 inch black plastic corrugated pipes located behind the office. The west pipe is also partially blocked. The flow causing this erosion appears to be coming from the hillside located to the east and above the pipes. As specified in the drainage plan, runoff from this area should be draining into the West Pond and not into the clear water diversion ditch. The area immediately above the pipe outlet should be graded to redirect this surface flow into the yard drain system. Photograph #4 shows the inlet of the westside drain at the canyon mouth. As seen it is partially blocked and should be cleaned. Photo #5 shows the terminus section of the clear water diversion ditch on the east side behind a building. There is a constriction in the ditch near the south end of the building which might limit the flow capacity of the ditch. All other ditches and pipes appeared in good condition. Except for the items cited above 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: Photograph #6 shows coal waste pile. The placement of new material in small lifts can be seen along the lower front edge of the pile. Compaction has been achieved by repeated passes of the heavy equipment used in moving the waste material. The flow path for water coming from above the pile, along the ditch at the top of the pile and then along the bottom of the pile can also be seen in photograph #6. There are no signs of structural instability on the waste pile. The fill on the waste pile has been constructed as specified in the design approved by the Division of Minerals and Geology.