B.C. has taken the leading role in the detection and mitigation of induced seismicity. New permit conditions were introduced in June 2016 requiring the presence of adequate ground motion monitoring during hydraulic fracturing activities and a ground motion monitoring report within 30 days of completing those activities. Amendments to the Drilling and Production Regulation introduced in June 2015 ensure wellbore operations are suspended if they trigger a Magnitude 4.0 or greater, and mitigation measures must be approved by the Commission before operations can continue.
In May 2018, the Commission issued a Special Project Order under section 75 of the Oil and Gas Activities Act. The Order was issued to address a series of low level seismic events arising from hydraulic fracturing in a ground motion monitoring area designated as the Kiskatinaw Seismic Monitoring and Mitigation Area (KSMMA). In October 2018, the Order was Amended to focus on nearby resident notifications and to specify which events require notification to the Commission.
On Nov. 29, 2018, a seismic event was widely felt in the Fort St. John area. In response, the Commission facilitated sub-surface research to better understand factors that contribute to induced seismic events. Experts in the fields of structural geology, hydrodynamics and geomechanics have concluded a preliminary study reviewing and assessing the quality of available public and proprietary datasets and, where data allowed, characterized some subsurface conditions (faults, pressures, rock properties and stresses) that could have influenced seismic events.
Questions and Answers about the KSMMA are available here.
The BC Oil and Gas Commission has launched three studies into induced seismicity, which resulted in the publication of three reports:
- Induced Seismicity Study in the Kiskatinaw Seismic Monitoring and Mitigation Area, British Columbia (2019)
- Report of Induced Seismicity in the Montney Trend (2014)
- Report of Observed Seismicity in the Horn River Basin (2012)
The preliminary KSMMA study identified major structural faults through the area, along with pressure compartments and stress trends that may have resulted. Some small faults and fractures that may contribute to seismicity were also mapped. More in-depth study will be done to further assess the potential for seismic activity within this region.
The Montney study found that during the study period 231 seismic events in that play were attributed to oil and gas operations – 38 induced by wastewater disposal and 193 by hydraulic fracturing operations. None of the recorded events resulted in any injuries, property damage or loss of wellbore containment outside of the formation and only 11 were felt at the surface.
The Horn River Basin study found that seismic events observed within remote and isolated areas of the Horn River Basin between 2009 and 2011 were caused by hydraulic fracturing operations, including 38 events recorded by Natural Resources Canada. None of these events resulted in any injuries, property damage or loss of wellbore containment and only one was felt at the surface.
Regulatory updates, permit conditions, as well as an expansion and improvements to the Canadian National Seismograph Network, were done as a result of Commission studies, including the Montney and Horn River Basin investigations.
The BC Oil and Gas Commission is a member of the B.C. Seismic Research Consortium, made up of other federal and provincial government agencies and industry. The Research Consortium was a result of a recommendation from the 2012 Report of Observed Seismicity in the Horn River Basin. In addition to the work being done by the Research Consortium, the Commission has worked closely with the University of British Columbia in the study of causes and mitigation with respect to induced seismic events. The Commission’s reports were subject to peer review by UBC researchers and other members of academia prior to publication. The Commission maintains a close relationship with UBC and other research institutions across North America through its association with other regulatory bodies.
What happens when there is an event?
If seismicity is detected in an area with oil and gas operations, either through the on-going monitoring of the Canadian National Seismograph Network or from the report of a felt event, the Commission contacts companies operating in the area with a request for more data, if available. The data is compared to the location and timing of the seismicity.
Resulting steps the Commission may take include requesting the deployment of dense arrays, changes to hydraulic fracturing parameters or suspending operations. Seismic events near disposal wells have resulted in the Commission contacting the well operator to discuss appropriate actions. In some cases, the operator voluntarily ceased disposal operations. In other situations, the Commission orders a dense array deployed to effectively determine the location and depth in relation to the well, to help ensure the disposal formation has not been compromised.