Treatment of Mine Drainage by Anoxic Limestone Drains and Constructed Wetlands

Abstract

Acidification is a universal problem at all mining sites in which oxygenated water comes in contact with sulfide minerals or other reduced sulfur compounds. An International Workshop was held in September 1995 at the Department for Inland Water Research of the UFZ-Centre for Environmental Research in Magdeburg on the limnology of lakes created by open-cast lignite mining, emphasizing the often observed geogenic acidification after oxidation of pyrite. Topics of interest were case studies on the limnology of acid lakes, e.g. bacteriologically enhanced processes related to heavy metal mobilization and acid generation, the ecology of sulfur-acidic lakes, and on the inorganic processes of acidification. Furthermore, concepts for the prevention and the abatement of acidification were addressed including the causes of acidification, and the options for reducing the output of acidified groundwater from overburden dumps, for acid control during the flooding of open-cast mines, and potential measures for induced in situ biological neutralization. This volume has 25 chapters including a chapter with results of group discussions about the topics mentioned above and further problems that were identified during the meeting. The monograph gives a baseline of the state of science on the worldwide problem of geogenic adidification of lakes following human mining activities, and how to handle this environmental problem.