#NOOTKA SOUND FISHING REPORT 2012 PLUS#

It is necessary to physically contain tailings because they are very susceptible to erosion, especially in high rainfall areas such as northern Vancouver Island.Īt Island Copper there were about 800 million t of waste rock and 400 million t of tailings generated over the life of the mine. In most mining operations the tailings are disposed of behind an earthworks dam that is constructed across a valley or other natural depression in the land.

#NOOTKA SOUND FISHING REPORT 2012 PLUS#

Mine tailings are more difficult to manage as they consist of a slurry of finely ground rock plus some residual portion of chemicals used during the milling operation.

Waste rock is generally trucked away from the mine and dumped in a designated area where it is eventually contoured into mounds and re-vegetated. With a low-grade ore such as Island Copper’s, less than 2% of the ground rock is recoverable mineral while the other 98% must be disposed of as tailings. Second, there are the mine tailings which are left over after the mineral concentrate has been extracted in the milling process. First, there is the overburden and waste rock that is removed in order to reach the ore. When developing an open-pit mine there are two main classes of waste that must be managed. The mine’s proximity to the sea presented some problems, however, with the disposal of waste.ġ.2 The Choices: Mine or No Mine, Land or Sea Tailings Disposal? The inlet is an extension of the Pacific Ocean and this provided the benefit of direct dockside loading of mineral concentrate onto ships bound for markets in Asia. The ore body lay beneath thick second-growth rainforest on a deep layer of glacial deposit and was situated immediately adjacent to the sea on the shore of Rupert Inlet. In deciding to proceed with the development of an open-pit mine, the company did not realize that the Island Copper Mine would become a landmark in the evolution of environmental policy and law in British Columbia and Canada. confirmed a viable ore-body with 280 million t of low-grade ore containing copper and molybdenum and trace amounts of gold, silver and rhenium. By 1969 an exploration program conducted by Utah Construction and Mining Ltd. In 1963, prospector Gordon Milbourne found signs of copper ore under two fallen trees near Rupert Inlet on the northern end of Vancouver Island (Aspinall, 1995). Two years after closure, it is now possible to review these impacts and to observe the prospects for ecosystem recovery following the cessation of waste disposal. The mine had been at the center of a controversy over the environmental impact of its submarine tailings disposal system for most of its 24 year ife. When the Island Copper Mine closed in 1995, after 24 years of continuous operation, it had produced 1.3 million t of copper, 31,000 t of molybdenum, 329 t of silver, 31.7 t of gold and 27 t of rhenium. Key Words: Mine Tailings, Heavy Metals, Marine Disposal, Environmental Monitoring, Mining, Pollution. This review highlights significant aspects of public policy decision-making, design of environmental monitoring programs, and questions of interpretation of monitoring program data.

In retrospect it appears that submarine tailings disposal has resulted in far less severe environmental impacts than if the alternative of land disposal had been adopted. It is also clear that widespread heavy metal contamination has not materialized.

It is apparent from the findings of the monitoring program that the mine tailings were dispersed more widely than was originally predicted. Following closure in December, 1995, the monitoring program is continuing in order to determine the extent of marine ecosystem recovery and re-colonization. The results of this program provide a thorough assessment of the environmental impact of submarine tailings disposal over the 24-year life of the mine. There was considerable controversy surrounding the development, public hearings were held, and as a requirement of the permit the company was obliged to carry out a comprehensive environmental monitoring program. In 1971 the government of British Columbia issued a permit for the Island Copper Mine to commence disposal of 33,000 tons per day of mine tailings into Rupert Inlet, a marine fjord on the northwest coast of Vancouver Island. Patrick Moore, Ph.D., Clem Pelletier, and Ian Horne, RPBio The Environmental Impact of Submarine Tailings Disposal at the Island Copper Mine on Vancouver Island:

Nootka sound fishing report 2012