The move comes three weeks after the AER reported an emulsion of oilsands bitumen and water had been released into an unnamed water body on the Cold Lake Air Weapons Range in eastern Alberta.
The watchdog says Canadian Natural (TSX:CNQ) must restrict steam injection, enhance monitoring and speed up clean up efforts at its Primrose and Wolf Lake projects, which use a method called high-pressure cyclic steam stimulation to extract the bitumen.
The AER ordered the suspension of steaming operations within the eastern part of Primrose earlier this year following three bitumen emulsion releases.
In late June, Canadian Natural reported a fourth release, prompting the AER to order CNRL to take further measures, including suspending steaming within one kilometre of the leak and restrict steaming throughout the northern and southern parts of Primrose.
Greenpeace campaigner Mike Hudema says it's troubling that it took four leaks for the regulator to take any "real action" and the incident raises questions about the safety of cyclic steam stimulation technology.
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