Syncrude said the fire at its Mildred Lake facility north of Fort McMurray was extinguished early Thursday morning.
An explosion and fire at the plant’s hydro-treating area Tuesday afternoon injured one worker who was taken to hospital in serious but stable condition.
READ MORE: 1 employee injured in explosion and fire at Syncrude upgrader north of Fort McMurray
The fire was isolated and under control Tuesday afternoon. Emergency responders were managing it as a controlled burn to burn off residual hydrocarbons.
“My deepest appreciation goes out to everyone who responded to this incident,” Syncrude CEO Mark Ward said in a news release.
“This remains a difficult time for our organization, but I am proud of the tireless efforts of our employees to ensure the safety and stability of our operations.”
The Syncrude employee who was injured remains in stable condition in an Edmonton hospital, the company said.
Now, the focus is on fully isolating the impacted area to make sure it’s safe for crews to go in and complete a damage assessment to come up with a repair strategy.
That will allow Syncrude as well as other agencies, including Alberta Occupational Health and Safety, to conduct full investigations to understand exactly what happened and help prevent future incidents.
READ MORE: Syncrude determines cause of oilsands facility fire, maintains ‘controlled burn’
On Wednesday, Syncrude spokesman Will Gibson said a line failure that caused treated naptha to leak sparked the fire. Naptha (flammable liquid hydrocarbon mixtures) is one of three hydrocarbons created in the bitumen-upgrading process. The fire started in plant 13-1, where hydrogen is added to product.
Syncrude said the rest of its operations were stable, with several upgrader units shut down or on reduced rates. Mining and extraction at both Mildred Lake and Aurora facilities are being paced to balance bitumen demand, the company said.