Grant: Collaborative Research and Development Grants

This project involves three universities, one research center, and four mining industry partners, and aims at the*characterization and treatment of contaminants of emerging concern (CECs) in mine effluents. In the context of*this study, the CECs in mine effluents include four categories: 1) new contaminants (e.g. Mn, Se, Sb); 2)*common contaminants (e.g. As, Cu, Zn), but with very low target concentrations in sensitive environments,*such as the cold climate; 3) difficult to treat contaminants (e.g. sulfate, salinity); and 4) nitrogen compounds*(ammonia, nitrites, and nitrates). Some of these contaminants are currently monitored via aquatic toxicity*assessment. Specific discharge criteria are expected in the near future, but they would be difficult to comply*with because of the operational challenges for CECs treatment, including a complex chemistry, persistency,*requirements of oxidizing or reducing conditions, lack of a proven BATEA, and insufficient knowledge as to*the optimal efficiency conditions with mixtures of contaminants and variable effluent quality. Thus, future*priorities of mining companies in water management should: 1) improve/develop sustainable treatment*technologies for CECs; 2) limit residual salinity creation; and 3) produce stable sludge. The study, which aims*knowledge advancing on the characterization of mine effluents and performance improvement of CECs*treatment processes, is centered around 3 objectives: O1) thorough characterization of effluents from 4 active*mines for CECs identification; O2) treatment of CECs, with focus on concentration and temperature; and O3)*evaluation of aquatic toxicity, before and after treatment of actual mine effluents containing CECs. The*methodology will consist of characterization of actual effluents, followed by treatability testing with mock and*real effluents, and toxicity evaluation of the optimal performance solution. A specific goal is to develop*protocols for accurate speciation analysis and treatment of CECs. The results obtained would allow, through an*advanced understanding of the technological and environmental aspects, better potential applications on a large*scale, on the sites of the industrial partners and elsewhere in Canada. The project will train 3 PhD and 2 PDF.