Seasonal and Operationally Linked Sulfur Geochemical Characterization of a Mine Oxidation Reservoir and its Inputs

The presence of sulfur oxidation intermediates (SOIs; e.g. S₂O₃^2-, SO₃ ^-, S0, etc.) in
mining wastewater is a significant industry-wide concern because of the potential for
acidification and toxicity of receiving water bodies, resistance to treatment and the
current lack of monitoring tools. Bacterially catalyzed transformation of sulfur species
under real world conditions remains poorly constrained, limiting the development of
biologically integrated indicators. As part of a larger project investigating the microbial
links to mine water S chemistry for the water system of Ni, Cu mines in Northern
Ontario, the objective of this investigation is to characterize the in situ S geochemistry of
Glencore’s Oxidation Reservoir (Onaping, ON) over seasonal, operational and annual
scales. As the Reservoir receives diverse water inputs from three mining companies,
waste rock, tailings lines and multiple watersheds, these are also being assessed over
seasonal scales to establish their contributions to observed Reservoir geochemistry.