| Ross Lake receives effluent discharged from the Hudson Bay Mining and Smelting Company (HBM&S) tailings ponds. The primary objective of this research was to monitor the concentration of zinc in the inflow and outflow of the North basin of Ross Lake using weekly surface water samples, porewater samples, sediment core samples, and bulk sediment core samples. The average concentration of zinc in the surface waters of the outflow of the North basin was higher than that of the inflow, 857 μg L−1 and 434 μg L−1, respectively. The saturation index for sphalerite (ZnS) indicates that this mineral may control the solubility of zinc and sulfur in the porewater. The average and maximum concentrations of zinc in the sediment of the North basin were 4.4% and 15%, respectively. Processes within the North basin, such as a seasonal release of zinc from the sediment, may contribute to the elevated concentrations. |
