A column experiment for groundwater remediation post-mine closure at the Wolverine Mine, Yukon

Abstract

Research is presented that evaluates a semi-passive treatment system for remediation of contaminated groundwater with elevated dissolved metal concentrations, including selenium and sulphate, at the Wolverine Mine, Yukon. Laboratory up-flow columns were used to treat simulated mine impacted waters. Five columns were filled with varying compositions of gravel and creek substrate organics, and were un-amended or amended with manure, sewage sludge, zero-valent iron, or wood chips and alfalfa. Selenium, sulphate and other parameters of concern were lowered in column effluents, most effectively by the control column and by the columns amended with sewage sludge. Column effluent metal and sulphate concentrations provided evidence that co-precipitation, adsorption and microbially mediated redox reactions were the predominant biogeochemical mechanisms operating within the columns. Based on this research, recommendations are made to further the design of a semi-passive treatment system that may be installed at the mine site upon closure.