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iii iiiiiiiiiiiii iii ,= .. :~„~=°,~ INSPECTION REPORT `: ~ ~~"{/ _ I' L~IV"70 ~.' Je j Site: National King Coal feline, Hesperus, Colorado .~~"~`'`~` 7/~~`..~''' , Inspected By: Don R. May, P.E., Project Engineer Inspection Date: Quarterly Inspection, June 30, 1998 A~ Ponds: The east and west sedimentation ponds and their embankments appear in good condition. The west pond is shown in photograph 1. Routine maintenance should be performed this summer. The outlet of the low flow pipe from the west pond is partially blocked and should be cleaned. All pipe inlets, outlets and spillways should be periodically cleaned. Drainage Ditches: The east side (below waste pile) and west side drainage channels appear in good general condition. With the reshaping of the waste rock pile, a new clear wafter diversion ditch, photograph 2, has been cut along the north side of the pile (east side drainage) and appears more than adequate. There is no ditch on the south side of the top of the pile. The design calls for a ditch along this side to catch runoff from the pile face and from the natural area above the pile. These areas can be seen on the left side of photograph 3. Flow form these areas will be diverted into the West Pond. The reclamation plan calls for an armored channel down the face of the pile on both the north and south sides. Once the face slope is modified these armored channels need to be completed. The drainage ditch behind the otd day sleeper, which carries runoff from the hillside behind the old scale house, mine entrance and fuel tanks needs maintenance. Photograph 4 is looking directly up the small ditch. As the photo shows, the ditch is overgrown and should be maintained from the very bottom to the top, along the old road. Due to recent removal of the trailer and culvert work near the bottom of this ditch a near vertical bank has been created that the ditch must flow over. A distinct channel should be formed and armored at this location. The yard drainage system appears to be operating properly however a few pipe inlets were partially blocked. All pipe inlets and outlets should be cleaned. 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 plan submitted to the Division of Minerals and Geology. Coal Waste Pile: The mine waste rock pile has been reshaped to conform to reclamation plan. The pile face can be seen in photograph 5 and top of the pile in photograph 3. The design slope for the pile face is 2.5:1. A survey performed on the day of the inspection showed that most of the pile was at or below the design slope. The upper'/. along the entire length is slightly steeper and should be flattened. A sketch