The use of anaerobic microbial consortia for the reduction of processing waste resulting from black coal mining operations was investigated. The biological production of methane (CH4) from coal refuse as well as from raw coal was considered as a potential method for gaseous fuel production. The reduction in the mass of the coal substrate at the completion of gas evolution was approximately 4%. Based on theoretical prediction however, the observed CH4 may not have been derived from the bioconversion of the coal molecule.