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BOWIE RESOURCES, LLC <br />Bowie No. 2 Mine <br />Coal Mine Waste Bank Nos. 1, 2 & 4 Inspections — 1 Quarter 2012 <br />On March 24, 2012, I performed a visual inspection of the Bowie No. 2 Mine coal mine waste banks in <br />accordance with Rule 4.10.2. This inspection includes Gob Pile Nos. 1, 2 and 4. <br />I, J. E. Stover, P.E., have a wide variety of experience in the design and construction of earth fill <br />embankments. Nothing was observed during the inspections that would indicate the piles have a <br />potential for failure. The gob disposal areas were dry to damp. All organic material and topsoil has <br />been removed ahead of the waste bank foundings. The upper diversion ditches were inspected with <br />no problems noted. <br />A significant amount of the gob pile no. 2 was covered with three feet of cover and one foot of topsoil <br />during the 4 quarter 2006. Most of the first and second benches were covered. Cover material from <br />gob pile no. 4 is stockpiled on the west side of pile no. 2. Cover material has been removed from the <br />east end of bench number two (pile no. 2). The slope inclination of the coal mine waste has been <br />increased in this area (5h:1v to 3h:1v. TR -61) <br />Most of the coal mine waste was generated from the preparation plant. Approximately 144,300 tons <br />of gob were hauled to the gob piles. Coal mine waste is to be placed in the pile in approximately <br />horizontal lifts no more than 24- inches thick. The coal mine waste is spread and compactive effort is <br />provided by a self propelled sheepsfoot compactor. Five (5) compaction tests were performed during <br />January. All but one of the tests failed. Three (3) compaction tests were performed in March. Two of <br />the three failed. The one that passed was a retest of a January test failure. A test passes if the test <br />attains at least 90% of the maximum dry density attained in a laboratory compaction test in <br />accordance with ASTM D698. There is still a lot of gob stacked for re- handling and compaction. This <br />material must be re- handled and compacted as soon as possible. Bowie did not make any headway <br />on the stacked gob during the quarter. Most of the gob sent to the pile during the quarter was stacked <br />for future re- handling. Bowie representative Bill Bear said Bowie has added personnel to work the <br />gob pile in the afternoon shifts and weekend shifts as well as another compactor during the day shift. <br />This along with recent good weather has allowed increased placement and compaction of existing <br />material <br />A failure of the gob pile no. 1 would probably not be a hazard to human life. The pile is located above <br />a large flat bench. The bench is approximately 80 to 150 -feet wide directly below the pile. <br />Additionally, the gob pile sediment pond is located below the pile. If the coal mine waste bank failed, <br />the material would very likely be contained on the bench below the pile and or within the gob pile <br />sediment pond. <br />A failure of the gob piles no. 2 and 4 would probably not be a hazard to human life. A residential <br />dwelling is located over 300 -feet below pile no. 2. The piles are located above Bowie Road. A failure <br />of the piles might damage Bowie Road but would not likely impact the residential dwelling. <br />Bowie has stacked gob for the last two quarters. I cannot certify the coal mine waste banks have <br />been constructed as permitted in the design approved by the DRMS. The Operatolowneibandle <br />the stacked material and get the material placed and compacted as soon as poiC • . g �.�'�: <br />• <br />it> t� ' / o l <br />V v <br />• Q- <br />• '� ' ` <br />James E. Stover I *: 1.9'231' Dave • <br />Colorado Profession .b ineer• / /, 24 <br />Registration No. 1923‘ I` { {{ ••. \y, <br />