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I. 3000 psi concrete shall be poured in place. A slight grade will be put on the finished concrete <br />to drain water off the plug. <br />J. During construction, the shaft opening will be protected by a substantial barrier as feasible. <br />All personnel working around the shaft collar will utilize harnesses and be tied off to prevent <br />falling. <br />8. 16 -foot diameter Bear Creek Return Shaft <br />A. As stated above, the Bear Creek return shaft has been isolated from the mine entries by falling <br />material that has plugged the shaft for a distance greater than 50 feet from the bottom of the <br />coal seam. <br />B. The first ring beam is just below the shaft collar. The second ring beam is approximately three <br />feet below the shaft collar and the third ring beam is approximately seven feet below the shaft <br />collar. In order to create a substantial concrete plug, the third ring beam will be used as a base. <br />C. During form construction, a pipe or hose will be lowered into the shaft, providing a small <br />amount of compressed air to ventilate and create movement to clear any methane leakage <br />coming from the mine workings. <br />D. Four steel beams, W8 x 24, will be lowered and set in place on top of the third ring beam. <br />These W -beams will be set parallel and approximately 3.5 feet apart. Their length will vary so <br />that they span the shaft opening. See attached drawing for details. <br />E. 3" corrugated steel Q -decking will be set in place over the beams and the perimeter will be <br />foamed in order to contain the concrete, once poured. If personnel are required to enter the <br />shaft to complete work, they shall be tied off at all times to prevent falling. <br />F. A mat of #9 rebar on 6" x 6" spacing will be placed about 4 inches above the Q -decking. <br />G. A second mat of #9 rebar on 6" x 6" spacing will be placed on top of the second ring beam. <br />H. A vent pipe, minimum 2" diameter, HDPE material, shall be set in place prior to pouring any <br />concrete. The vent pipe shall extend a minimum of 15 feet above the final designed grade and <br />shall be secured as necessary to prevent tipping. <br />1. No cutting or welding will be performed directly over the shaft. <br />J. 3000 psi concrete shall be poured in place. A slight grade will be put on the finished concrete <br />to drain water off the plug. <br />K. During construction, the shaft opening will be protected by a substantial barrier as feasible. <br />All personnel working around the shaft collar will utilize harnesses and be tied off to prevent <br />falling. <br />9. After the Elk Creek shafts have been completed and the concrete has cured, dirt or other <br />incombustible material will be placed in the slopes, against the block seal, for a minimum distance <br />of 25 feet. The material will be placed as high to the roof as practical without damaging the block <br />seal. Positive ventilation will be utilized over any equipment. Until final reclamation, the portal <br />entries will be adequately fenced or protected and posted with conspicuous signs prohibiting the <br />entrance of unauthorized persons. <br />10. The proposed start date for sealing is October 19, 2015, however, this date depends on plan <br />approval by MSHA and contractor procurement. Completion of all seals is expected within six <br />weeks after commencement. <br />11. This plan, once approved, will be posted at the work area, and it shall be reviewed with all <br />workers. <br />