ABSTRACT
Mining in permafrost-affected areas raises unique issues that need to be addressed to minimize the environmental impact of mining. The exploitation and disposal of sulfidic tailings can lead to acid mine drainage (AMD) including acidification and leaching of heavy metals. Permafrost features that influence the deposition of sulfidic waste include processes within the active layer that produce pathways for reactant and contaminant transport, barriers such as snow and ice covers, and low temperatures that slow most chemical and biological processes. Primary issues for disposal of sulfidic mine tailings are summarized and strategies for controlling the oxidation of sulfide minerals at sub-zero temperatures are discussed. Results from a case study in Canada illustrate the possibilities of keeping tailings permanently water-saturated or frozen, thereby controlling AMD. Future research should focus on AMD generation rates at sub-zero temperatures and solute migration in frozen media.
