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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, January 23, 2003 <br />Ponds: The east and west sedimentation ponds and their embankments and outlets <br />appear in good condition. The west pond is shown in photograph 1. Routine cleaning <br />will be required sometime this spring. <br />Drainage Ditches: The east side and west side drainage channels appear in good <br />general condition. The ditch that parallels the access road around the coal pile, in the <br />vicinity from the office to the waste pile is filling with sediment. Photo 2 shows the east <br />side drainage just above the mine adit and photo 3 shows the outlet of the pipes that <br />collect water from the main yard area and discharge near the parking lot. Both of these <br />ditches are in good condition. The lower yard is shown in photo 4. All other ditches and <br />drainage structures were inspected and appear in good operating condition. There are <br />no apparent drainage problems on the site. All drainage features have been constructed <br />and are operating as stated in the drainage plan submitted to the Division of Minerals <br />and Geology. <br />Coal Waste Pile: There are no visible signs of structural instability on the waste pile. <br />The toe of the waste pile has been cut to a steep angle to make more room for coal <br />trucks, particularly near the bottom of the first (from office) rock lined channel. This <br />oversteepening of the toe could result in instability. This area should be regraded to the <br />design slope of 3:1 and compacted to 90% proctor. It is important that the waste <br />material be placed in lifts not to exceed 12" to 18" and that compaction results in the <br />density stated in the design report It is not possible to determine this by visual <br />inspection and therefore the density should be periodically checked by measurement. <br />Care should be taken to assure a 1 % cross slope on the top of the pile. All rainfall and <br />snowmett should readily flow to the collection ditch on the east side. Because of the <br />rough nature of this surface it may need to tie kept somewhat steeper during <br />construction. <br />It is recommended that the upstream end of the water pile underdrein be located and <br />marked. As the pile grow this task will become more difficulty. <br />Except for the items mentioned above the fill on the waste pi{e has been constructed as <br />specified in the design approved by the Division of Minerals and Geology. <br />