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L. Pre -shift and on -shift examinations will be made of the work areas and records kept in <br />accordance with 75.360 and 75.362. Additionally, as a part of this site-specific plan, gas tests <br />will be made for CH4, CO, and 02 on four hour intervals, from both the slopes and the return <br />shaft, and the results recorded in the examination books. These gas tests are required only <br />when personnel are working underground and are not required around the clock or on days <br />when no one is working. <br />M. If the gas tests show elevated levels of CH4 or CO, miners will be removed from the area, <br />MSHA shall be notified, and bag samples will be taken to verify gas concentrations. Elevated <br />levels shall be considered CH4>2.0% and CO>50 ppm. <br />N. Conveyor belt structure will have to be removed from the belt entry slope prior to any <br />construction work on the seals in that entry. <br />O. The proposed location for the slope seals is approximately 100 feet inby the portal opening. A <br />small concrete pad will be poured at that location to provide a solid and level footer for the <br />seal to be erected upon. <br />P. The ventilation tubing installed in the slopes will be connected to a blowing fan, which will be <br />started just prior to any seal construction. The blowing fan will provide a minimum of 10,000 <br />CFM in the slope entry. The fan will be located to prevent re -circulation of ventilating air. <br />The end of the tubing shall be within 20 feet of the seal location. <br />2. Slope Entry Seals <br />A. Once the blowing fan is in place and running, the concrete footers have been poured and cured, <br />and the conveyor structure has been removed from the belt entry, the construction work on the <br />seals may begin. <br />B. Seals will be constructed with 8" x 8" x 16" solid concrete blocks, laid in a transverse pattern <br />so that the joints are staggered, using a wet -bed mortar construction technique between all <br />joints. The minimum thickness of the seal will be 16". There shall be a center pilaster that <br />measures 16" wide by 32" deep. <br />C. MSHA approved sealant or mortar will be applied to the entire surface of each seal wall. <br />EXCEPTION: On the inby face of the seal, sealant or mortar shall be applied as high off the <br />mine floor as possible. Wedging may be done no more than 6 inches on top of the blocks. <br />Boards shall be placed in a layer of sealant or mortar. <br />D. There will be no surveillance pipes, water drainage pipes, methane drainage pipes, or P -traps <br />installed in the seal. Water drainage is controlled at the portal opening. <br />E. Seals in both slope entries may be constructed simultaneously depending on the availability of <br />personnel. Alternatively, work may leap frog between the two seals so that they may be <br />completed at approximately the same time. <br />F. NOTE: Prior to shutting off the Elk Creek Fan, the nuts and bolts tying the fan housing to the <br />shaft collar will be loosened or removed. Nuts or bolts tying the fan plenum panels together <br />may also be loosened or removed to facilitate future removal. <br />G. When the final row of blocks is being set in place, the Elk Creek fan will be turned off and the <br />explosion doors will be opened or removed. Positive ventilation will be maintained over <br />miners through use of the blowing fan and tubing. The final blocks shall be set in place and <br />the seals completed without delay. <br />H. At all times when personnel are not working underground, access to the underground mine <br />will be adequately fenced or protected and posted with conspicuous signs prohibiting the <br />entrance of unauthorized persons. <br />I. Both of the slope entry seals will be completed prior to working on any of the shafts at Elk <br />Creek. <br />2 <br />