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• _. ; <br />INSPECTION REPORT <br />Site: National King Coal Mine, Hesperus, Colorado <br />Inspected By: Don R. May, P.E., Project Engineer <br />Inspection Date: Quarterly Inspection, August 12, 2000 <br /> <br /> <br /> : <br /> -~~ <br />:r <br /> <br /> <br />'. ~ E <br />C <br /> <br />~E <br /> <br /> <br />$~P 0 5 2000 <br />Ponds: The east and west sedimentation ponds }h?ir gr~hankments anPl~C~!iof44irtarals~a~i~y <br />in good condition. The west pond is shown in photograph 1 with standing water from <br />recent thunderstorms. It is evident that the pond has been cleaned out since the last <br />inspection. The ditch entering the pond is undergoing erosion (bottom left of photo 1) <br />and a small head cut has formed. This reach of channel should be stabilized. The east <br />pond appears in good condition. <br />Drainage Ditches: The east side and west side drainage channels appear in good <br />general condition. Photographs 2 and 3 show yard drainage features which are <br />performing well. A{I other ditches and structures were inspected and appear in good <br />operating condition. All drainage features have been constructed and are operating as <br />stated in the drainage plan submitted to the Division of Minerals and Geology. <br />Coal Waste Pile: There are no visible signs of structural instability on the waste pile. <br />Photograph 4 shows a portion of the pile face, above the access road, near the lop. As <br />seen the slope on the face formed by newly placed material appears to exceed the <br />design slope of 3:1 (horz:vert). This slope should be surveyed and regraded to meet the <br />design slope. <br />The top of the pile is shown in photograph 5. It appears to conform to the design <br />geometry. It is important that the waste material be placed in lifts not to exceed 12" to <br />18" and that compaction results in the density stated in the design report. It is not <br />possible to determine this by visual inspection and therefore the density should be <br />periodically checked by measurement. <br />Rill formation on the front face of the waste pile slope is shown in photograph 6. There <br />are a number of these small erosion channels ranging from a few inches to one foot in <br />depth. These will continue to gro~.v unless stabilized. The highwall and other slopes at <br />the site appear stable. <br />Except for the items mentioned above the fill on the waste pile has been constructed as <br />specified in the design approved by the Division of Minerals and Geology. <br />