Submarine tailings disposal: mining's problem with waste
Safe disposal of mine waste, including tailings, is generally recognized as the single largest environmental challenge facing the mining industry worldwide and a major expense for mining companies. Modern open-pit mining has a very high waste-to-product ratio (roughly 99 tonnes of waste to each tonne of copper, and even far more waste in gold mining), making waste the major product of mining. The Canadian mineral industry generates about 650 million tonnes of waste per year.1 The storage of this waste poses significant engineering challenges. All over the world, tailingsdams are leaking, or breaking, and seeping toxins on a daily basis; but recent environmental and social disasters in Romania, Guyana, Spain, and the Philippinescaused by tailings-dams that bursthave served to focus public attention on this problem.