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ill 1 •• ~r INSPECTION REPORT '-``y~..'~~'~ ,'aa`:`~t~';. •` ~' ~ ~' ,({~~. ~,-.{[D~ : c~ . n'seected B "IDon R. Mal cP.E ~ProecCEnoineer _ ~.,- Inspection Date: Quarterly Inspection, March 26, 1998 ~~`''~~~.E `~''' Ponds: The east and west sedimentation ponds and their embankments appear in good condition. The west pond is shown in photograph 1 with standing water from spring runoff. At the staff gage sedimentation has been minimal but some infilling near the inlet (upper end of the pond) has occurred. Routine maintenance should be performed this summer. The east pond appears in good condition. The Swale across the entrance road between the ponds that diverts runoff from the road into the east pond can be seen if photograph 2 is carefully studied. It is formed by the hump in the road located in the middle, left of the photo. Photograph 3 shows the new pipe laid just west of the office (background). Drainage Ditches: The east side and west side drainage channels appear in good general condition although they are covered by snow which precludes detailed inspection, photograph 4. The drainage ditch that carries diverted, clear water behind the office to the drainage in Hay Gulch is shown in photograph 5. Photograph 6 shows the toe of the waste pile slope. A small ditch should exist here. Drainage in the yard appears to be working well. All other ditches and structures were inspected and appear in good operating condition. All drainage features have been constructed and are operating as stated in the drainage plan submitted to the Division of Minerals and Geology. Coal Waste Pile: There are no visible signs of structural instability on the waste pile. Photograph 6 shows a portion of the pile. The slope on the face appears to exceed the design slope of 3:1 (horz:vert). This should be confirmed and adjustments made to the face as needed to assure the design slope is met. In addition, it is important that the waste material be placed in lifts not to exceed 12" to 18" and that compaction results in the density stated in the design report. It is not possible to determine this by visual inspection and therefore the density should be periodically checked by measurement. The highwall and other slopes at the site appear stable. As reported last quarter, it appears that waste material is being generated in larger amounts that initially expected and hence the waste pile is approaching the final design volume prematurely. This concern is being address by the redesign of the waste pile. Construction is scheduled to begin in the next month. Except for the items mentioned above the fill on the waste pile has been constructed as specified in the design approved by the Division of Minerals and Geology.