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75.316 Ventilation System and Methane and Dust Control P'_an <br />Amendment <br />General: <br />The exhaust ventilation shaft will be installed in the bleeder <br />entries for the Aiorthwest longwall panels. The shaft will <br />have a 8 feet lined diameter. An exhaust fan will be <br />installed on the shaft following its completion. <br />Preparation: <br />The development for the approaches and the shaft bottom area <br />has been comoleted. <br />Shaft Excavation ar_d Lining: <br />During the excavation of the shaft bottom and the shaft, the <br />ventilation will b2 directed and regulated to the return to <br />ensure a minimum quantity of 15000 CFM at the shaft bottom. <br />The methane content will be monitored at the drill rig and <br />underground during the excavation of the shaft. <br />The raise drill will be equipped with a centrifugal far. <br />(specifications listed in section 77.1900 Shaft Construction <br />Plan) attached to the drill steel via the water swivel and a <br />bull hose. The fan will drag the atmosphere from the level of <br />the raise borer head thru the drill steel and exhaust it at <br />the well head. During reaming, the methane concentration of <br />the fan exhaust will be checked continuously with a methane <br />detector. The inlet of the fan will be equipped with a flame <br />arrestor to prevent a problem should the fan fail. If the <br />methane concentration at the centrifugal fan reaches 1's, <br />reaming will stop and a air compressor will be attached to the <br />system and the discharge blown thru the drill steel. At 10 <br />minute intervals, the fan will be reattached to determine if <br />the methane content is less than 1%. If the methane level is <br />satisfactory, the fan will remain in use and reaming will <br />resume. If the methane concentratior, reaches 1.5~, the raise <br />drill will be de-energized and the personnel underground <br />notified. The compressor will continue to discharge thru the <br />drill steel to dilute the methane to less than 1's before <br />reaming continues. The compressor is capable of delivering <br />approximately 500 cfm at 110 psi. <br />Underground, a continuously reading methane menitcr will be <br />placed in the return to monitor the methane concentration a:_d <br />alert the personnel at the drill rig and underground. If the <br />methane content in the return reaches 1.5°s, reaming will stop <br />and a air compressor will be attached to tae dri'_liag system <br />and the discharge blown thru the drill steel and additicr:a'_ <br />underground ventilation gill be supplied to diiuta the <br />Y methane. <br />iiS•7-i Exhaust Shaft 3 t~?~ROV~D L'i91~ tii i 1 ~ ~P i~ +j ?~ ~t <br />