Foos, A., J. Baxter, B. Dingman, J. Firth, M. Gebregiorgis, P. Glover, A. Hajdarwish, A. M. Harper, J. Maximovich, C. Miller, S. Starr, K. Traugh, H. Trembczynski, 1999, Geochemical analysis of coal mine drainage, East Canton, Ohio. Geological Society of America Abstracts with Programs, v 31, No. xx, p. xx

ABSTRACT

Water samples of acid mine drainage from an abandoned, underground coal mine in East Canton, Stark, Co. Ohio, were collected and analyzed for temperature, conductivity, pH, oxygen reduction potential (ORP), dissolved oxygen (DO), Cl-, SO4-2, PO4-3, NO3-, H2S, Na, K, Mg, Ca, total Fe, Fe+3/Fe+2, Mn, Al, and Si. The stream investigated was receiving water from the abandoned mine opening and a wetland which drains a second mine opening. The stream channel was coated with an amorphous iron-hydroxide precipitate (yellowboy) which reached a thickness > 1 meter. Water from the mine opening had a pH of 3.4, TDS of 1844 mg/l, ORP of 363 mvolts, and total Fe of 107 mg/l. In contrast water from the wetland had a pH of 2.9, TDS of 1805 mg/l, ORP of 496 mvolts, and total Fe of 48 mg/l. There was a positive correlation between ORP and DO (R=.96); ORP and Fe+3/Fe+2 (R=.71). A negative correlation existed between ORP and total Fe (R=.96); ORP and pH (R=.90). These trends reflect absorption of O2 from the atmosphere, oxidation of Fe+2 to Fe+3, followed by precipitation of amorphous iron-hydroxide which caused a slight decrease in the pH. Changes in the chemistry of the water downstream reflected a combination of equilibration with the atmosphere, and mixing between the waters of the mine opening and the wetland.