Lysimeter investigations on uranium tailings at CANMET

CIM Bulletin, Vol. 75, No. 846, 1982

G.M. RITCEY and M. SILVER, Extractive Metallurgy Laboratory, Mineral Sciences Laboratories, CANMET, Energy, Mines and Resources Canada, Ottawa

The processing of uranium ores produces tailings that could constitute environmental problems. At most operations the tailings are dumped into a designated area, with the ultimate acid drainage occurring if sulphides are present, together with the release of metal constituents to the rivers and streams. If the chemical reactions occurring within the tailings could be predicted, perhaps methods could be developed to either increase or decrease the rates of reaction. One such study has been in progress at CANMET during the past three years. The paper describes the use of lysimeters containing low-grade and complex uranium tailings to determine the effects and interactions of bacteria, sulphides and solvent extraction organics on the release of radionuclides and on acid production. A simulated rain cycle nine-fold the normal was used and the lysimeters were subjected to timed intervals of light and darkness. As a result, the tests simulated a 25-year period.

Keywords: Mineral processing, Lysimeters, Tailings, Uranium tailings, Environmental control, Elliot Lake, Rabbit Lake, Midwest Lake, Key Lake, Radionuclides.