British Columbia's energy regulator has confirmed that a 4.6 magnitude earthquake in northeast B.C. in August of this year was caused by a nearby fracking operation.
"This seismic event was caused by hydraulic fracturing," said Ken Paulson, CEO of the B.C. Oil and Gas Commission. Paulson said fewer than one per cent of fracking operations trigger seismic activity, and those quakes tend to be low magnitude and cause little damage.
The quake struck in August, about 110 kilometres northwest of Fort St. John, near a gas fracking site operated by Progress Energy.
Hydraulic fracturing or "fracking" is a process that involves pumping a mixture of water, sand and chemicals underground at high pressure to fracture rock and release trapped natural gas.
Studies have linked fracking with earthquakes in the U.K., Oklahoma, and in B.C.
Largest fracking-related quake
The epicentre of the August quake was three kilometres from the Progress Energy fracking site. The operation shut temporarily immediately after the quake but soon restarted with continued monitoring.
Fracking operations have previously triggered small earthquakes in B.C. In the U.S., the disposal of frack waste has triggered larger quakes. But scientists said last summer that the 4.6 magnitude August quake may be the largest in the world caused by hydraulic fracturing.
No one was injured in the earthquake and there was no damage reported, but shaking could be felt for several kilometres.
Experts say it is unlikely any fracking-related earthquakes in the future will cause damage.
"This level of earthquake, although sounds scary, but in terms of the actual seismic damage, magnitude 4.6 is very unlikely to cause significant damage," said Honn Kao, a research scientist with the Geological Survey of Canada.
In a written statement, Progress Energy says it takes the incident very seriously, and is closely monitoring seismic activity near its frack sites.
Meanwhile, B.C.'s energy regulator says it continues to closely monitor seismic activity and B.C.'s gas fields, and that it's still business as usual.
Balance between development and public safety
Kao says there are existing industry protocols in place regarding fracking-caused earthquakes.
"We've already had a meeting together — workshop together with everybody to discuss the best practice protocol that's currently in place."
He says the regulator's acknowledgement that this 4.6 earthquake was caused by fracking means those protocols can now be updated to better protect the public.
"The key issue really is if we have all the necessary practice protocol in place so that we can set the level to a certain acceptable risk. Then the community will feel much less afraid and therefore we can reach a very nice balanced approach between the development and the public safety.