A field investigation of tailings resuspension in a shallow water cover

摘要

Shallow water covers for preventing acid production in tailings are based on the principle of minimizing oxygen availability. Resuspension of material from the tailings bed may result in increased oxidation and metal releases since dissolved oxygen is at near saturation levels in the water cover. Resuspension can be caused by waves and currents strong enough to mobilize the surface of the tailings bed. Tailings resuspension was measured with sediment traps in the Upper Cell of the heath Steele site near Miramichi, New Brunswick, Canada. Although significant amounts of resuspended tailings were collected in all traps, analysis of resuspended solids and bed tailings suggests that for the observed wind conditions resuspendsion did not occur at location where the water cover depth was greater or equal to 1.0 m. Currents were likely responsible for the transport of resuspended tailings from shallower areas to locations where the water cover was deeper than 1.0 m.