Canadá: Companies could be allowed to release treated tailings pond water into Athabasca River by 2023

Oil companies could be allowed to release treated water from tailings ponds into Alberta waterways by 2023 when new provincial and federal regulations are set to take effect.

The releases would be part of a larger strategy to deal with a buildup of 1.3 billion cubic metres of water and toxic mining byproducts that have accumulated in pools on the province’s landscape. Alberta Energy Regulator rules say all oilsands operations need a tailings management plan, in which companies explain how they intend to leave the land close to how they found it within a decade of closing a mine. A September 2019 AER report says of the eight management plans companies have submitted, two are insufficient and need more work.

Right now, companies are forbidden from releasing water from tailings ponds into natural bodies of water. The companies want permission to release the treated water because, one day, the mines are going to close and all that water has to go somewhere, said Rodney Guest, director of water enclosure in regional development for Suncor. “If you want to do integrated water management and set yourself up for successful closure and reclamation, returning water is something that should have been enabled for the industry a long time ago,” he said.

Toxic yogurt

Three or four barrels of water are needed to extract each barrel of bitumen from the oilsands. Most of the water is recovered and recycled, but some can’t be. The sheer volume of sludgy byproducts and water in the ponds in the Athabasca region of northeastern Alberta make it a unique problem, said Nina Lothian, Alberta associate regional director and director for fossil fuels at the Pembina Institute.

“It’s a huge impact to the land and the air and the water, locally, in the lower Athabasca region,” she said on Wednesday. The volume is also expanding, as some companies produce tailings faster than they can remediate them. The total volume of tailings ponds in the Athabasca region grew by about 17 per cent between 2014 and 2018, according to the AER.

In 2017, they covered 220 square kilometres of northeastern Alberta. What’s left after oil is removed, tailings have a consistency of yogurt and are made of sand, silt, clay, water, and residual bitumen. They also contain naphthenic acids, which are toxic to wildlife, heavy metals, chlorides and salts, Lothian said. The turbidity of the pond water also makes it uninhabitable.

Time is an enemy. The slurry contains fine particles that don’t easily settle out on their own, Lothian said. Spinning them in a centrifuge or leaving them to dry can be expensive and energy intensive, she said. Oil companies know tailings are a challenge. Syncrude, which operates the Mildred Lake mine near Fort McKay, has invested $3 billion during the last decade researching how best to cope with tailings, spokesman Will Gibson said Friday.

Clearing the water

Syncrude, which has the largest share of Athabasca tailings ponds, has since 2018 run a test project at the mine attempting to treat the water thoroughly enough to put in the Athabasca River. Testing started in labs 15 years ago, and they’ve been scaling it up ever since. The company treats the contaminated water with petroleum coke — similar to a Brita water filter, Gibson said — which removes clay and dissolved organic compounds.

Syncrude is working with federal regulators to monitor the quality of the cleaner water over time to see if it’s suitable to go into the river, which is about five kilometres away. The AER has approved an expansion of Mildred Lake, which will ultimately produce more tailings. The company proposes to cope with other tailings using a technique called “water capping,” in which clean water is layered over untreated tailings that are left to settle in a spent mine pit. That approach is not yet approved by the AER, which wants the company to submit an updated plan, and a backup approach, by 2023.

Gibson said the company has a contingency plan, and that the approach is successful in smaller-scale tests. “We’re taking this very seriously,” he said. “We’re making sure that it works so we’re taking our time to make sure it’s done right.”

Since late 2018, Suncor has tried an approach called permanent aquatic storage structure (PASS) to liberate its water. The process adds a coagulant to neutralize and aggregate the fine, charged particles suspended in tailings, Guest said. An added polymer helps those clumps stick together in threads, which make them heavy enough to sink and settle more quickly. The separated water could then be recycled or, eventually, released into the river, if approved, he said.

Before anything new goes into the Athabasca River, it’s key companies consult with the communities downstream, including people in the Fort Chipewyan and Fort MacKay areas, Lothian said. “A regulatory framework of this complexity and importance will take several years to complete and will include extensive engagement of interested parties, industries, Indigenous peoples, municipalities and other stakeholders,” said Jenn Gearey, a spokeswoman for Environment and Climate Change Canada, in a Wednesday email.

Alberta’s ministry of environment and parks is also developing provincial regulations in concert with the federal government.

By: Edmonton Journal