Fractured Vertical Wells Versus Horizontal Boreholes for Methane Drainage in Advance of Mining U.S. Coals

Jones, A.H., Ahmed, U., Abou-Sayed, A.S., Mahyera, A., and Sakashita, B.
Paper presented at Aus.I.M.M. Illawarra Branch Symposium, May 1982.


Ventilation has long been the primary means of controlling methane emissions in underground coal mines. However, as mining has progressed into gassier areas of U.S. coal basins, supplemental means of methane control have become of interest, if not a necessity, for continued safe and productive mining operations. This paper describes the history and technology of methane drainage in the United States and other countries. The methane drainage technology developed in European countries is a valuable resource since their longer history of mining has already forced mine operators to deal with methane emission problems only now being experienced in the United States. Methods for assessing the need for methane drainage and the data required for planning and implementing an appropriate system are reviewed. The effectiveness of the various technologies for reducing methane emissions underground and/or the in-place gas content of individual coalbeds is illustrated with case studies. In addition to the safety and productivity gains to be realized from methane drainage systems, the potential for commercialization of coalbed methane is discussed.