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INSPECTION REPORT ~av °~ ~~~ ""_q%:~',< car (. v~ l;s~ =f+• ?_35551/ _?. Site: National King Coal Mine, Hesperus, Colorado ~J{'~ ~ ~ P ~ ::,. ,;~~.` Inspected By: Don R. May, P.E., Project Engineer //S y~ ~j ~ g:~~s •••• .• • `~ ~~~ Inspection Date: Quarterly Inspection, May 4, 2003 1/ `7t+++++n~~~~.~ Ponds: The east and west sedimentation ponds and their embankments and outlets appear in good condition. The west pond shown in photogreph 1 is in need of routine leaning. The outlet works are dean and operable. Drainage Ditches: The east side and west side drainage channels appear in good general condition. The ditch that parallels the access road around the coal pile, in the vicinity from the office to the waste pile is filling with sediment and should be leaned. Photo 2 shows the west side rock line drainage ditch near the top. Some coal is present along the length of this dean-water ditch. Care should be taken avoid contamination. The ditch on the east side of the top of the waste pile is in good shape. The upper and lower yards are shown in photos 3 and 4 respectively. Drainage in these areas is working well. All other ditches and drainage structures were inspected and appear in good operating condition. There are no apparent drainage problems on the site. 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: There are no visible signs of structural instability on the waste pile. As reported in previous inspections, the toe of the waste pile slope has been cut to a steep angle to make more room for the coal storage pile. This is shown in photos 5 and 6. This oversteepening of the tce could result in instability. The biggest impact is that runoff from the slope will tend to initiate erosion rills as the water flows over this short but seep reach. These rills will moves up the slope getting progressively deeper and destroying existing vegetation. URimately this area should be regraded to the design slope of 3:1 and compacted to 90% proctor and revegetated. A temporary, alternate solution would be to armor the toe of the slope with rods or some other material that will prevent the erosion rills from forming. The top of the waste pile is in good condition. It is important that the waste material be placed in lifts not to exceed 12" to 18° and that compaction results in the density stated in the design report. Recent density measurements performed by Lambert and Associates (3/06/03) at four locations resulted in densities that varied from 94% to 100%. It is recommended that the upstream end of the water pile underdrain be located and marked. As the pile grows this task will become more difficulty. Except for the items mentioned atwve the fill on the waste pile has been constructed as spedfied in the design approved by the Division of Minerals and Geology.