The acid production potential of a coal was related to its paleoenvironment (environment of deposition) as interpreted from the overlying strata. Within the Appalachian coal field of eastern Kentucky, coals and associated strata were characterized as either back-barrier, lower delta plain or upper delta plain. Samples from various paleoenvironments were analyzed for sulfur content and pyrite types (reactive versus stable). Samples from the back-barrier, lower delta plain sequence had a relatively higher percentage of reactive pyrite than the seams within strata of upper delta plain. Both environments produced coals of similar total sulfur contents and both contained varying percentages of framboidal pyrite. Although reactive pyrite was present in seams of both paleoenvironments, a differing natural water chemistry caused acid mine drainage to be associated with the back-barrier, lower delta plain strata and never with the upper delta plain strata. This study showed that the pyrite distribution and, more importantly, the water chemistry producing acidic or neutral drainages, were correlative with the paleoenvironment of the coals and associated strata.

"Grant no. R-802597-02." Includes bibliographical references (pages 73-76). Microfiche.