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CAM MINING, LLC Munger Canyon Mine Coal Mine Waste Bank Inspection - 2"tl Quarter 2007 On June 28, 2007, I performed the required quarterly visual inspection of the Munger Canyon Mine coal mine waste bank in accordance with Rule 4.10.2. I, J. E. Stover, P.E., have a wide variety of experience in the design and construction of earth fill embankments. Nothing was observed during the inspection that would indicate the pile has a potential for failure. The gob disposal area was dry. Previous inspections by the undersigned noted that all organic material and topsoil has been removed ahead of the waste bank founding. The upper diversion ditch was inspected with no problems noted. The pile was being covered with 3.5 feet of non-toxic cover at the end of the quartet ~ - _ -t --_-~ .~ --_- - - -- __------ - -- - The first coal mine waste, 1,270 tons, were placed in the pile during the period November 23`~ through November 29, 2004. The coal mine waste was leveled during the second quarter 2005. Approximately 880 tons were hauled to the gob pile and compacted during April 2006. The Operator hauled approximately 620 tons of material to the pile during the quarter (March 2007) from the McClave Canyon Mine material drying area. During the 2nd quarter 2007 approximately 3750 tons were hauled to the gob pile. The material was generated from the portal reclamation project. Coal mine waste is to be placed in the pile in approximately horizontal lifts no more than 24-inches thick. The coal mine waste is spread and compactive effort is provided by a front-end loader. Five compaction tests were taken June 5°i to confirm the material hauled during March 2007 was compacted. All tests passed. Another four tests were taken on June 14, 2007 to confirm the material placed from the portal reclamation project was adequately compacted. All tests passed. A test passes if the test attains at least 90% of the maximum dry density attained in a laboratory compaction test in accordance with ASTM D698. Compaction test results are enclosed. A failure of the pile would probably not be a hazard to human life. The pile is located in a remote area well away from human habitation. I certify that to the best of my knowledge and belief, that the fi d Sher aspects of the Munger Canyon Mine refuse pile have been constructed ~ ° ~..~,e design approved by the DRMS. ,~~o: ~~ ~T°.,F.~ Recommended maintenance: None 0 ~0~ ~ 7 (~~ U~e~O ~ ,~a~ 15230 Aa ~! 9 e !A e ~ ~ 7 a°"'L40 James E.°~ifer°..°••a°a~~z~ Date Colorado P~Sf~g~angineer Registration No. 19230