The underground gasification of coal is a method which combines extraction and conversion of coal into a single step, thus eliminating the need for mining and coal processing equipment and gasification reactors. In situ coal gasification is a process which should be considered as a competitor with shaft mining but not with surface mining. The successful application of this method would provide a low Btu gas (100-300 Btu/SCF) which can be readily treated for sulfur compounds and particulates and at the same time eliminate many of the health, safety, and environmental problems associated with conventional deep mining of coal.