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,: <br />~. <br />iiiiiiiiiiiiiiiiiii <br />INSPECTION REPORT <br />Site: National King Coal Mine, Hesperus, Colorado E ~`~ ~ ~ ~~ ~ es} <br />_;ct? 2 b 5 : <br />Inspected By: Don R. May, P.E., Project Engineer ~ ~:, ~//7 ~ ~;~ <br />Inspection Date: Quarterly Ins ection, October 22, 2000 ~~~~~s "••J••°~ ~~~~~~ <br />P qis/~NAI ~:..ao <br />Ponds: The east and west sedimentation ponds. their embankments and outlets appear <br />in good condition. The west pond is shown in photograph 1 with standing water. As <br />mentioned on the last inspection, the ditch entering the pond is undergoing erosion <br />(bottom left of photo 1). It has cut quite a deep channel in the area adjacent to the main <br />access road and a small head cut has formed. Although this poses no immediate threat <br />this reach of channel should be stabilized. T!;e east pond appears in good condition. <br />Drainage Ditches: The eastside and westside drainage channels appear in good general <br />condition. Photograph 2 is looking down the yard road from near the mine entrance. As <br />seen, except for small puddles, the yard is dry, even after relatively heavy showers. The <br />buried drainage culverts running under the yard should be checked for clogging. Photo 3 <br />shows the ditty water ditch that runs along the south side of the top of the waste pile. As <br />seen, it is well formed and in good condition. The channels running from the top of the <br />pile to the bottom, especially the north side are eroding and need stabilizing as <br />mentioned in previous reports. All other ditches and structures were inspected and <br />appear in good operating condition. All drainage features have been constructed and are <br />operating as stated.in the drainage plan submitted to the Division of Minerals and <br />Geology. <br />Coal Waste Pile: There are no visible signs of structural instability on the waste pile. The <br />pile continues to grow as shown in photograph 4. This picture was taken from the top of <br />the pile looking back towards the mine. Recent fill is seen on the left side of the access <br />road. Photograph 5 was taken from the access road looking up at this new fill area. 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, it necessary, <br />regraded to meet the design slope. <br />The top of the pile appears to conform to the design geometry. It is important that the <br />waste material be placed in lifts not to exceed 12" to 18" and that compaction results in <br />the 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 />Rill formation on the front face of the waste pile is unchanged from the last inspection. <br />The highwall and other slopes at the site appear stable. It is recommended that the <br />upstream end of the water pile underdrain be located and marked. As the pile grow this <br />task will become more difficulty. <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 />