GENERAL50934 - Laserfiche WebLink

Home Browse Search

/' •' r DEGA.SIFICATICN PROGRAM FOR THE HAWK' S NEST MBA J .. .~,_, 'l, l~.~l Methane levels in the Hawk's Nest Mine have increased significantly because of larger amounts of coal being exposed by the more efficient mining techniques now used there. The mine ventilation system has been unable to maintain their levels of gas anission within reasonable safety limits. To avoid recurrence of methane ignition, similar to the recent Dutch Creek Colorado mine disaster, an emeLyency degasification program has been implemented at the Hawk's Nest Mine. The project includes ~~letion of 18 drill holes from the surface into the active mine workings, as well as into areas now being developed for ;mm~ri;ate extraction. Each hole will be drilled 8 to 10 inches in diameter, depending on drilling conditions, as well as on in-mine gas levels, and will be cased with 5 1/2 to 7 inch diameter threaded and coupled steel pipe. The bottom 300 to 400 feet of the casing will be slotted, permiting methane to be pumped to a surface oollectiai system where it will be vented to the outside. Aocess to many of the drill holes is on existing roads, haaever, some of the more critical holes, which penetrate into areas where gas levels are dangerously high, must be provided by way of Healy constructed roads. These new roads will be built to approximately 12 to 14 foot widths and within reasonable grades which will allow safe travel as well as be coir~patible with environmental considerations. All of the roads are expected to be left open during mining beneath that immediate area and will be maintained to allay servicing of surface pumping equipment and disposition of the gas. 4bpsoil from the drill sites will be stockpiled and will be used after drilling and venting is c-cmpleted for reclamation of the sites. The seed mixture to be used will be one which has been approved by OSM as well as by the CMLR.