Coal deposits in the Appalachian and Midwest Coal Regions consist primarily of thin relatively deep seams of swelling bituminous coal, but little scientific effort in the United States has been directed toward underground coal gasification in these important industrial areas. In Europe, however, major work is under way on underground coal gasification in thin, deep seams of swelling coal. The principal investigator and a graduate student are participating in field tests in Belgium and supporting laboratory experiments in Germany. Mathematical models are being developed to interpret these experimental data, and a better understanding of the underground coal gasification process is emerging. This understanding is essential for evaluating potential problems, for devising solutions to such problems and for designing field tests.