WILD COAL FIRES
Dr. Glenn B. Stracher
Department of Science and Mathematics
East Georgia College
Friday, November 14, 2003, 3:15 p.m.
Ben Bandy Conference Room
Center for Applied Energy Research
Toxic vapors, heat, and ground subsidence necessitate caution when collecting samples of coal fire gas and associated condensates for laboratory analysis. Gas samples can be conveniently extracted from surficial vents and fissures using a hand pump, Teflon intake and exhaust lines, and impermeable Tedlar collection bags. Solid condensation products can be obtained by using spatulas, scoops, and plastic or glass vials. During collecting, it is essential to avoid contaminating the condensate with rock or soil upon which the gas has condensed. Condensates identified from Inner Mongolia, Indonesia, and Colorado include: millosevichite, allunogen, tschermigite, anhydrite, salammoniac, godovikovite, haüne, zaherite, zincovoltaite, orthorhombic sulfur, gypsum, pentlandite, and hazelwoodite. Condensates from the Wuda coal fire in China and the Centralia mine fire in Pennsylvania exhibit vesicular and flow textures characteristic of a gas to liquid transformation followed by a liquid to solid transformation. Microarthropods of the Order Collémbola, with furcula in tact, have been discovered in association with gas vents at the Centralia fire whereas yet to be identified microarthropods have been discovered at the Healy coal fire in Alaska. Thermodynamic loops are useful for deriving pressure-temperature stability diagrams for gas-condensation equilibrium. The diagrams have environmental implications in that they suggest the tendency of pollutants to condense on the surface as opposed their absorption in the atmosphere.