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q0 RE <br />R. 07 <br />INSPECTION REPORT <br />r ln...?4? .?J ?Tt• <br />)Izt <br />?'•?.? ?? ?•' , <br />Site: National King Coal Mine, Hesperus Colorado <br />Inspected By: Don R. May, P.E., Project Engineer <br />Inspection Date: Quarterly Inspection, 3rd Quarter- Sept. 22, 2009 <br />Ponds: Both ponds appear in good condition. Photo 1 shows the west pond. During the last <br />inspection it was noted that the overflow spillway was eliminated during reconstruction. This <br />oversight has been remedied. Photo 2 shows the reconstructed spillway. Although the ponds <br />appear to be constructed properly, at some point, the design elevations, and dimensions of the <br />low level outlet, spillway, pond bottom and embankments should be surveyed to assure <br />continued compliance with the design plans. The inlets, outlets, and embankments of both <br />ponds were inspected and except for the items mentioned above they appear in good condition. <br />Drainage Ditches: Since the last inspections, construction work has extended the rock lined, <br />clear water drainage ditch (north side of refuse pile)up the hillside to the new crest of the pile <br />and then adjacent to the pile, paralleling the top surface, to the most upstream end of the pile. <br />There has always been a ditch in this location but in the last six months the top of the pile has <br />been reconfigured, rerouting the access road, regrading the top, and reconstructing the ditches <br />as shown in photo 3. The rock lined ditch from the bottom to the crest of the pile is in excellent <br />condition. However, the portion of the ditch running from the crest, adjacent to the top of the pile <br />and extending to the upstream end of the pile appears to be graded in the wrong direction. <br />Visually, this section appears as if water would flow east toward the upstream end of the waste <br />pile. If this is the case, water will pond in the ditch along the top of the pile. This could result in <br />saturation of the fill material and ultimately could lead to slope failures on the face of the pond. A <br />survey should be completed to assure that the slope of the ditch invert conforms to that <br />specified in the design. The drainage ditch on the other side (low side) of the pile has also been <br />reconstructed and is in excellent shape, photo 5. <br />Drainage in and around the upper and lower yards is working well and both are in good shape. <br />The entrance to the pipe that intercepts the drainage near the_mine adit is partially blocked and <br />should be cleaned.. All other drainage channels on the site were inspected and are in good <br />condition. Routine maintenance should be carried out to ensure that the entrances to all pipes <br />are free of debris. <br />All drainage features, with the exception of those cited in this report, have been constructed and <br />are operating as stated in the drainage plan submitted to the Division of Minerals and Geology. <br />Coal Refuse Pile: The top surface of the refuse pile has been reconstructed and appears in <br />excellent condition. When the survey of the ditch and ponds is performed the slope of the top <br />surface of the pile and the low side ditch should also be checked for conformance to the plans. <br />It is also recommended that compaction tests be performed to assure compliance with the <br />design specifications. <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.