Environmental Considerations for Wet Mining Peatlands in Northwestern Ontario

Signi cant changes in water quality were detected using a Before-After-Control-Impact (BACI) experimental design. Porewater showed increases in pH, alkalinity, conductivity (including Ca, Mg, K, Na), some metals (Sr, Ba, Mn, Fe) and total nitrogen (TN) in the mined and restored plot. Change in surface water total mercury (THg) was linked to total suspended solids (TSS) and limited to active phases of wet mining. The season mining ceased, TSS and THg concentrations in impacted surface waters were similar to reference site water (<5 mg L1 and