Influence of Uranium Mill Tailings On Tree Growth at Elliot Lake

CIM Bulletin, Vol. 71, No. 800, 1978

D.R. Murray, Agronomist, Elliot Lake Laboratory, Mining Research Laboratories, CANMET, Department of Energy, Mines and Resources,, Elliot Lake, Ontario

A four-year study was carried out to determine the ability of coniferous trees to aid in the reclamation of uranium tailings at Elliot Lake, Five species were planted: white cedar, white spruce, jack pine, scotch pine and red pine. More than 570 bare-root, two-year-old seedlings were planted on bare tailings and in areas of established grasses. A further division was made between areas of coarse and fine tailings.Over-all survival and growth of the trees has been far below expectations based on previous experience with several varieties of grasses. The criteria for assessment have been per cent survival and yearly growth as determined by plant height. Pine was superior, with 68% survival when planted in bare coarse tailings, 45% for vegetated coarse tailings and 34% for vegetated fine tailings. Cedar had the worst survival rates at 49%, 14% and 7% respectively. No species survived on bare fine tailings.The survival and growth of the coniferous trees have been related to species, environmental conditions and tailings properties.

Keywords: Uranium, Waste reclamation, Environmental control, Tailings, Tree growth, Elliot Lake, Mine wastes.