The Lotts Creek coal mine fire is burning in abandoned works of the Pennsylvanian Hazard No. 9 coal, Perry County, Kentucky. Over the few months separating sampling trips, the fire showed a definite migration to the south. Several vents sampled on the first trip were extinct on the second trip. The flux of major gases varies from 1100 to 440,000 mg/s/m(2) CO2 and < 100 to 12,000 mg/s/m(2) CO, with the gas temperature being one of the principal drivers of the emissions variations; the higher the temperature, the more CO2 produced. Mercury, also showing wide variation, from 45 to 740 ng/s/m(2), could not be measured at all vents due to temperature limitations inherent in the instrument. In addition to CO2, CO, and Hg, a number of gases among the volatile aliphatic and volatile aromatic compounds are emitted in potentially dangerous amounts.