Worker presumed dead after incident at Suncor oil sands site

A worker is missing and presumed drowned after an incident at Suncor Energy Inc.'s giant Base Plant mining and upgrading facility in northeastern Alberta.

The worker, an employee of contractor Christina River Construction, is believed to have been operating a bulldozer that broke through the ice on a frozen tailings pond, Suncor spokeswoman Erin Rees said in a Jan. 14 email. The incident occurred Jan. 13. Suncor's emergency services team responded at approximately 3 p.m. local time. The bulldozer operator was still unaccounted for approximately 24 hours later.

"Our thoughts are with the family, friends, and coworkers of this individual," Rees said. "Supporting the safety and wellbeing of our people remains our number one priority and we have activated critical incident stress debriefing resources."

The incident occurred at an inactive site and there has been no impact on Suncor's operations, Rees said. Alberta's Occupational Health and Safety department is reviewing the accident.

Oil sands tailings are a mixture of water, sand, fine silts, bitumen and other hydrocarbons leftover after tarlike bitumen is processed into refinery-ready crude. The residue is stored in a series of human-made lakes called tailings ponds where the solids are allowed to settle. Toxic metals in the water and a hydrocarbon sheen on the ponds make them uninhabitable for fish and toxic to birds and other wildlife.

Alberta's tailings ponds cover approximately 77 square kilometers, or about 30 square miles, and about 220 square kilometers when the structures that contain them are added, according to data compiled by the University of Calgary. Approximately 1.5 barrels of tailings waste are produced for each barrel of bitumen extracted from the oil sands, the university said.

The Base Plant accident was the second fatal incident at a Suncor facility in recent weeks. On Dec. 28, 2020, a man and a woman were killed when a truck collided with a bulldozer at the Fort Hills oil sands mine, approximately 63 kilometers north of the Base Plant. Fort Hills is co-owned by France's Total SA and Canadian miner Teck Corp.