In the oil sands, tailings are a mixture of water, sand, clay and residual bitumen, and are the by-product of the hot water treatment process used to separate the oil from sand and clay in oil sands mining operations. Tailings and tailings ponds are not unique to the oil sands - many mining and other industries create tailings and manage this material using ponds.
Tailings are stored in large engineered dam and dyke facilities called tailings ponds.
Tailing ponds enable water to separate from sand, clay and bitumen for re-use in bitumen extraction. Water is continuously recycled from tailings ponds back into the extraction process, reducing use of fresh water from the Athabasca River and other sources. Oil sands producers recycle 75% to 87% of water used.
Oil Sands Tailing Ponds Management
Tailings ponds can remain part of an active mine operation for 30 to 40 years, either for tailings deposits to settle, or for storage and water recycling. Reclamation of the industry’s first tailings pond, Suncor’s Pond One (Wapisiw Lookout), completed surface reclamation in 2010. Strict regulations and a comprehensive monitoring program are in place to mitigate potential impacts.
The Government of Alberta requires all oil sands operators to have plans in place to convert fine tailings to reclaimable landscapes. Recognizing that tailings are an important part of mining activity, this is a detailed policy to manage existing and future tailings production. Project-specific targets are set for each operation to ensure tailings are ready to reclaim within 10 years of the end of the mine’s life.
Canada’s oil sands industry is improving tailings ponds management by monitoring active tailings ponds and developing technologies to move ponds into reclamation sooner.
Mine operators employ many methods to keep waterfowl from landing on tailings ponds, such as cannons, scarecrows, decoy predators and radar/laser activated acoustic deterrent systems like those used at airports to scare birds away. Operators also reclaim bitumen from the surface of the ponds to reduce the risk of oiling if birds land despite the deterrents. Even with these precautions, birds have landed on the ponds and drowned as a result of oiling.
Reclaiming Tailings Ponds
Since tailings ponds can be part of mine operations for 30 to 40 years, the government requires financial guarantees for each mining project to ensure reclamation plans are carried out. Oil sands mining operators contribute to the Mine Financial Security Program, a contingency fund held by the government for reclamation of land impacted by mines. These funds are used if operators do not carry out their reclamation plans. To date, there has never been a need to draw on this fund, so it continues to grow.
Did You Know?
$1.2 billion has been invested in tailings reduction technology by oil sands operators.
Canada’s Oil Sands Innovation Alliance (COSIA) is an alliance of oil sands producers focused on accelerating the pace of improvement in environmental performance in Canada’s oil sands through collaborative action and innovation. COSIA’s Tailings Environmental Priority Area (EPA) is focused on improving the management of oil sands tailings.