The use of shallow water cover to flood potentially acid-generating tailings and previously oxidized tailings is one of the most effective methods of reducing the environmental impacts of reactive sulfide tailings disposal. Although the transfer of oxygen to the flooded tailings by molecular diffusion is extensively curtailed, wind-induced waves arid associated pressure-driven countercurrents can erode and resuspend tailings and compromise water quality. The paper examines the cohesive character of tailings from two sites in Canada and presents a method for analyzing resuspension, based on the critical shear stress of the tailings, instead of just the grain size. The method is applied to one of the sites and the results show that resuspension may be completely eliminated under water cover depths up to 2.5 m and design winds with a 100-year return period. The condition of no resuspension is very stringent and may be relaxed by allowing some particle entrainment in the water cover within acceptable regulatory limits.
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