Nexen Energy said Wednesday that a pipeline spill near its Long Lake oil sands facility in Canada last week could take months to investigate.
According to Reuters, Nexen said pinpointing the cause of the 31,500 barrel emulsion spill will most likely take months.
Emulsion is a mixture of produced water, sand and bitumen.
The leak was detected on July 15 south of the Fort McMurray oil sands hub.
Nexen senior vice president of Canadian operations Ron Bailey told Reuters the leak probably began after June 29, following a pipeline cleaning with water.
The company has not determined exactly when the spill began or why its leak detection system failed.
The spill size is currently estimated at 5,000 cubic meters of emulsion, or about 31,500 barrels, and affected an area of about 16,000 square meters, mostly within a compacted pipeline corridor.
There were no injuries reported and the pipeline has been isolated.
The company, a subsidiary of China’s CNOOC, has shut in the Kinosis oil sands project where the spill occurred and plans to prioritize cleaning up and investigating the spill over restarting operations.
Bitumen produced at Kinosis is processed and upgraded at the Long Lake facility.
“We’ve actually shut in everything at Kinosis and our priority is not to bring Kinosis back on production. We will be focusing on understanding the root cause of any failure here and the reliability of our systems before we ever start up this system again,” Bailey told Reuters.
Nexen said on Monday that a deceased duck was discovered on the western side of the spill site.
The company believes the duck had been at the spill site before many of the company’s wildlife deterrents were put into place.
“Nexen sincerely regrets that this incident has occurred. We remain committed to minimizing the impact the spill has on the environment and wildlife. We are working closely with the Fish and Wildlife department of Alberta Environment and Parks to continue developing a comprehensive wildlife mitigation plan,” Nexen said.
The company added that it will share its wildlife mitigation plan with the public after it has been approved.
Production capacity at Long Lake is 72,000 barrels of bitumen per day, according to Nexen.