2010-10-07_REPORT - C1996083 - Laserfiche WebLink

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BOWIE RESOURCES, LLC Bowie No. 2 Mine Coal Mine Waste Bank Nos. 1, 2 & 4 Inspections - 3rd Quarter 2010 On October 1, 2010, 1 performed a visual inspection of the Bowie No. 2 Mine coal mine waste banks in accordance with Rule 4.10.2. This inspection includes Gob Pile Nos. 1, 2 and 4. 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 inspections that would indicate the piles have a potential for failure. The gob disposal areas were dry. All organic material and topsoil has been removed ahead of the waste bank foundings. The upper diversion ditches were inspected with no problems noted. A significant amount of the gob pile no. 2 was covered with three feet of cover and one foot of topsoil during the 4th quarter 2006. Most of the first and second benches were covered. Cover material from gob pile no. 4 is stockpiled on the west side of pile no. 2. Cover material is being removed from the east end of bench number two (pile no. 2) in order to facilitate increasing the slope inclination from 5h:1v to 3h:1v. (TR-61) Most of the coal mine waste was generated from the preparation plant. Approximately 47,400 tons of gob were hauled to the gob piles. 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 self propelled sheepsfoot compactor. Thirty- one (31) compaction tests were performed during the quarter. 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. The test that failed on June 24th (#4532) was reworked, tested and passed on the July 1st. One test taken on August 11th failed (#4551). The area was reworked and passed on August 25th. A failure of the gob pile no. 1 would probably not be a hazard to human life. The pile is located above a large flat bench. The bench is approximately80 to 150-feet wide directly below the pile. Additionally, the gob pile sediment pond is located below the pile. If the coal mine waste bank failed, the material would very likely be contained on the bench below the pile and or within the gob pile sediment pond. A failure of the gob piles no. 2 and 4 would probably not be a hazard to human life. A residential dwelling is located over 300-feet below pile no. 2. The piles are located above Bowie Road. A failure of the piles might damage Bowie Road but would not likely impact the residential dwelling. I certify that to the best of my knowledge and belief, that th mine waste banks have been constructed as permitted in t 10. v2 U.S ects of thecoal by the ERMS. f e ® a ®?t' o James Colorado Registratioi :over ???ff???6gnaf??!