2014-05-28_INSPECTION - C1996083

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May 21, 2014 C- 1996 - 083 /Bowie No. 2 Mine SLB The East Diversion ditch above Gob Pile 42 was in good condition. The D50 of the rip rap in place along the steep stretch of this ditch was estimated to be 12 ", consistent with the design information of Appendix B of Volume IX of the approved permit application package. On the eastern end of the ditch, just prior to the southward turn, material from the native slope above the ditch has sloughed into the rip rap. This area will need to be monitored and maintained as necessary should additional material slough into and compromise the flow area of the ditch. Ditches F23 and F15 were in good condition. The outslope of Bench 4 (Point 1 on map excerpt below) was measured at 29 %. The measured slope is in compliance with the approved design requirement of no steeper than 3:1 (33 %) on Figure 1 of Volume IX. Groh Pile #3 Refuse material was being excavated from the southwest drying area for placement and compaction in the central area of the pile. Material in the northeastern area of the pile was being rehandled /turned over for drying prior to grading and compaction operations. Operations on Gob Pile 43 were being conducted in compliance with the operation and reclamation plan in the approved permit application package. The northern edge of the Gob Pile 43 drying area was pooling water; an excavator regraded the material for positive drainage during the inspection. Ditch J8 -1 needed to be regraded to ensure positive drainage toward culvert J8. An area of pooling was observed along the ditch at Point 7 on the map excerpt below. There were a few rocks from the berm along ditch J3 that had fallen into the ditch that should be cleared out. The inlet to culvert J4 was partially obstructed with sediment. An excavator was making its way over to the area to clear the ditch and culvert. The underdrain was flowing at a very low rate into ditch J3. Gob Pile 44 Cover material was being placed on Gob Pile 44, on the west end. Topsoil will be redistributed after cover fill placement, and the pile will be seeded this fall. Reclamation of Gob Pile 44 was being conducted in accordance with the approved plan. The operator indicated that the cover material depth would be verified during placement with GPS equipped dozers, comparing the elevation of the in -place cover material to the elevations of the pile that were established during the May 2013 survey conducted during the review of TR -75. The West Diversion ditch above Gob Pile 44 was inspected, and found to be in good condition. The ditch had been recently maintained. The tie -in to the natural drainage (Gulch C) on the west end of the ditch was in good condition. The grade on a section of this ditch was measured by CDRMS at -2 %. The approved design (Appendix Number of Partial Inspection this Fiscal Year: 18 Number of Complete Inspections this Fiscal Year: 3 Page 4 of 20