Tailings impoundments

McGregor, R.G., Blowes, D.W., Jambor J.L., Robertson W.D. 1998. Mobilization and attenuation of heavy metals within a nickel mine tailings impoundment near Sudbury, Ontario, Canada. Environmental Geology, 36, 305-319. 

Solids - Waste piles, Tailings impoundments and Stream sediments. 

The long-term performance of synthetic liners is not known, and even in the short term can be affected by the presence of subsoil settlement, rock punctures, seam splitting, or entrapped air bubbles (Gee et al. 1990). The possible failure of synthetic liners creates an additional problem if they are the only barrier used in the tailings impoundment instead, they should be seen as a short-lived barrier that is only one part of a multilayer system. 

Laboratory and field studies are needed to further our understanding of the behaviour of radionuclides and other contaminants in the tailings impoundment. This understanding also needs to be extended to the complex set of interactions between the tailings, infiltrating water, liners, and underlying sediments so that the effectiveness of the rehabilitation scheme can be evaluated. 

McCreadie, H., Jambor, J.L., Blowes, D.W. (1998) Geochemical behavior of autoclave-produced ferric arsenates jarosite in a gold-mine tailings impoundment, in Waste Characterization and Treatment (ed. W., Petruk), Society for Mining, Metallurgy, and Exploration, Littleton, Colorado, pp. 61-78. 

Moncur, M.C., Ptacek, C.J., Blowes, D.W. et al. (2002) Impact of mine drainage on a lake from an abandoned tailings impoundment. Abstracts with Programs. The Geological Society of America, 34(6), 51. 

Any liquid, gaseous or aerosolic waste discharged in the environment. Generally, it is a complex mixture. For example, wastewaters include mine water effluent, mill process effluent, tailings impoundment area effluent, treatment pond or treatment facility effluent, seepage and surface drainage. Volume 1(9,10,14), Volume 2(2,5). 

Wunderly M. D., Blowes D. W., Frind E. O., and Ptacek C. J. (1996) Sulfide mineral oxidation and subsequent reactive transport of oxidation products in mine tailings impoundments a numerical model. Water Resour. Res. 32, 3173-3187. 

The occurrence of secondary Si02- H20 has been observed in several tailings impoundments, predominantly as amorphous hydrated pseudo-morphs after biotite. Cristobalite [Si02] has also been detected in the pseudomorphs. Partial replacement of various other minerals by amorphous silica has also been observed. 

At the Matchless pyritiferous deposit in Namibia, huntite [CaMg3(C03)4] occurs within high-pH zones in an oxidized tailings impoundment (Dill et al., 2002). The high-pH zones are sandwiched between low-pH layers, with phyllosilicate-rich layers acting as aquitards that impede vertical movement and homogenization of the pore waters. 

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