(Reuters) – Canada’s Imperial Oil IMO.TO, a subsidiary of ExxonMobil, spilled crude oil into a process-water lagoon at its Mahihkan plant in northern Alberta, contaminating a flock of geese, the Alberta Energy Regulator (AER) said on Wednesday.
The spill of around six barrels of oil, which took place on Monday, is the latest environmental lapse by the oil sands company. Earlier this year it emerged that toxic tailings water had been seeping for months from Imperial’s Kearl mine, and a second separate leak occurred in February.
Twelve Canada geese became smeared with oil after landing on the lagoon, the AER said in an incident report on its website. All the birds have been removed from the lagoon and taken to a specialist site for cleaning and rehabilitation.
“The oil release was due to an operational upset that was immediately addressed. The recovery of oil from the lagoon is ongoing,” the AER report said.
Wildlife cannons and flagging have been deployed around the lagoon, which is under 24-hour surveillance by Imperial, and containment booms have been placed in the water to stop the oil from spreading further.
Imperial spokeswoman Lisa Schmidt said there were various levels of staining on the geese, but all were alive.
In an update posted to its website on Wednesday, Imperial said it was continuing monitoring around its Kearl site to determine if further work to mitigate the months-long tailings seepage, first spotted in May 2022, was needed.
“We need to take additional time to see if what we put in place, these mitigations, are working as intended,” Schmidt said.
In the last week a dead frog and two dead minnows were found near the seepage site and were collected for additional testing, Imperial said.
The company finished expanding its seepage interception system with extra drainage, pumping wells and vacuum systems in late June.
