Our monitoring in the Fox Creek area has helped us confirm that induced earthquakes are more likely to occur when companies conduct hydraulic fracturing in deeper geological formations like the Duvernay.
We have developed earthquake (seismic) monitoring and reporting requirements for hydraulic fracturing operations in the Brazeau reservoir area, where the Duvernay formation exists thousands of metres below the surface. This area, roughly 50 kilometers southwest of Drayton Valley, includes the Brazeau hydroelectric dam.
Earthquakes induced by hydraulic fracturing have not been observed or reported near the Brazeau dam. While there is no immediate risk to public safety or the environment, we have developed these requirements as a precaution to limit the potential for an induced earthquake to happen near the Brazeau dam.
Companies in the area must comply with Subsurface Order No. 6, which imposes seismic monitoring, reporting, and setback requirements in the zone. The order requires operators to manage the hazard of induced earthquakes before, during, and after hydraulic fracturing.
The order does not allow hydraulic fracturing to take place within five kilometres of the Brazeau dam if drilling operations are targeting the Duvernay Formation.
The order also prohibits hydraulic fracturing within three kilometres of the Brazeau dam if drilling operations are targeting formations above the Duvernay Formation, which includes the Cardium, Rock Creek, and Falher Formations.
In addition to the order, we have a number of requirements in place to protect subsurface and wellbore integrity during hydraulic fracturing. Directive 083: Hydraulic Fracturing – Subsurface Integrity addresses the hydraulic fracturing risk to subsurface well integrity.
Companies operating near the Brazeau dam must follow a “traffic light” system to monitor for seismic activity.
- Seismic event of less than 1.0 local magnitude (ML): no action is required by the operator.
- Seismic event of 1.0 MLor greater: the operator must immediately report the event to the AER and implement their response plan.
- Seismic event of 2.5 MLor greater: the operator must immediately cease operations and report it to us. They cannot resume operations without our approval.
Our staff use over 50 seismic monitoring systems to measure and research earthquakes and seismic activity across Alberta. To help ensure the safe, orderly, and environmentally responsible development of energy resources, we will continue to monitor and evaluate the performance of Subsurface Order No. 6.
As we continue to learn more about the Duvernay Formation and the relationship between hydraulic fracturing and seismic activity, we will amend the subsurface order if evidence suggests that adjustments are needed.