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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, 1st Quarter- 2009 <br />Ponds: Photograph 1 shows the west pond. As seen sediment is building up in the <br />bottom near the entrance section. The height of the embankments appears to have <br />been increased which would in turn increase the storage volume. However, The <br />elevation of the overflow outlets are set relative to a designed embankment height and <br />the elevation of the bottom. This means that any increase in storage volume gained <br />from raising the embankments cannot be effectively utilized without recomputing and <br />setting the outlet elevations. Because of this it is still necessary to clean the sediment <br />from the bottom of the ponds on a regular basis to assure adequate capacity. <br />Photo 2 shows the reconstructed embankment on the downstream end of the pond. <br />Although it look very nice the overflow spillway is missing and was presumably removed <br />or buried during the work on the embankments. This is an important part of the pond <br />design and must be reconstructed as per the design plans. Setting the spillway crest <br />elevation will required a survey and hence would provide a good opportunity to check <br />the volume of the pond and the elevation of the low flow outlet. <br />The inlets, outlets, and embankments of both ponds were inspected and except for low <br />flow outlet on the big pond which is partially blocked (see photo 3) and the missing <br />spillway, they appear in good condition. <br />Drainage Ditches: The clean water drainage ditch adjacent to the waste pile and on the <br />top of the pile is in good condition except for the very top portion where the access road <br />runs adjacent to the ditch. In this area the ditch has very little shape and should be cut <br />to assure the size specified in the plans. The ditch on the other side of the pile is in poor <br />condition. No clearly formed ditch exists for most of the pile length. Along the upper <br />portion it appears that flow would actually be in the wrong direction, see photo 4. This <br />area needs to be reconstructed as per the design plans. The entrance to the culvert <br />coming from the natural drainage near the mine entrance is partially blocked. All other <br />drainage channels on the site were inspected and are in good condition. Routine <br />maintenance should be carried out to ensure that the entrances to all pipes are free of <br />debris. <br />Drainage in and around the upper and lower yards is working well and both are in good <br />shape. All drainage features, with the exception of those cited in this report, have been <br />constructed and are operating as stated in the drainage plan submitted to the Division of <br />Minerals and Geology. <br />Coal Waste Pile: As seen in photo 5 there has been a significant volume of new <br />material placed on the pile. The design report calls for a 3:1 slope on the front face and <br />all material placed in lifts not to exceed 12" and then compacted to 90% of the modified