Steaming process led to leaks at Alberta oilsands site: watchdog

CALGARY—Alberta’s energy watchdog is blaming bitumen leaks at an oilsands site in northern Alberta on the steaming process employed by the operator.

The Alberta Energy Regulator (AER) said the steaming strategy, as well as wellbore issues, were the two main “enabling factors” that led to the bitumen emulsion releases in 2013 at the Primrose project in northern Alberta operated by Canadian Natural Resources Ltd. (CNRL).

Four bitumen releases at the site have been reported to the AER since May 2013, leading to the watchdog imposing restrictions on steaming activity at the site in June 2013 pending review.

After receiving both an independent technical review and a causation report from CNRL, the AER said four main factors led to the releases.

The independent review found CNRL’s injection of “large volumes of steam at fracture pressure in closely spaced wells was a fundamental cause” of the releases.

“Our assessment of the reports leads us to believe that these flow-to-surface events can be prevented if proper mitigation measures are put in place,” said AER president and chief executive Jim Ellis said in a statement.

“That said, the AER is not prepared to approve a return to full operations at these sites until all potential risks are addressed and proper requirements are in place to avoid a similar incident. This will require a gradual, step-by-step approach that allows us to manage those risks.”

In March, the AER denied an application by CNRL to resume steaming operations in a “restricted zone” near the site of the leaks.

The watchdog came under fire from critics in April after it approved CNRL’s request to resume steaming at the Primrose site near Cold Lake, Alta., albeit no closer than one kilometre from the leaks.

The AER said the operations must be conducted at low pressure.

CNRL and the independent review board are set to submit final reports to the AER in September.