2011-10-17_REPORT - C1996083 (3)

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BOWIE RESOURCES, LLC Bowie No. 2 Mine Coal Mine Waste Bank Nos. 1, 2 & 4 Inspections — 3rd Quarter 2011 On September 26, 2011, I 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 4 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 has been removed from the east end of bench number two (pile no. 2). The slope inclination of the coal mine waste has been increased in this area (5h:1 v to 3h:1v. TR -61) Most of the coal mine waste was generated from the preparation plant. Approximately 94,754 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. Sixty -seven (67) compaction tests were performed during the quarter. Fifty -nine (59) of the sixty -seven (67) tests passed. A test failure on June 20th (pt 4629) was reworked, tested and passed. All final tests met or exceeded project specifications or were otherwise accepted by site client representatives, with the exception of moisture - density test Nos. 545 and 547, taken September 13, 2011. Retests of these tests will be performed next 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. There is still a lot of gob stacked for re- handling and compaction. This material must be re- handled and compacted as soon as possible. Bowie made some headway re- handling the stacked gob during the quarter. 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 approximately 80 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 mine waste banks have been The Operator must re- handle as soon as possible. knowledge and belief, that the fill 'otht aspects of the coal constructed as permitted in th� by the DRMS. the stacked material and get d ni nal `pla - ed'and compacted 'kJ ,,o a ° c4)-'; •' `moo a fl o 0 P � °o� f0 ` /Z' /` /o 0 James veg000 �c �`ao Date Coloradod6$jon ,Engineer Registration No... 19