The small town of Fox Creek in northern Alberta may have broken the world’s ‘fracking earthquake’ record with the 4.4-magnitude shaker that hit last month.
The most probable cause, according to Alberta’s energy regulator, was nearby gas fracking operations. The recent quake was on many people's mind as they listened to a presentation in Ottawa on the shale gas "bonanza" happening across North America today.
Fracking and earthquakes
“There seems to be a link between the volume of water [used in fracking] and seismic activity,” Denis Lavoie, a research scientist with the Geological Survey of Canada (GSC) told an audience of parliamentarians, experts and the general public in Ottawa during a presentation yesterday.
The talk was part of the ‘Bacon & Eggheads’ monthly morning lecture series put on by the Partnership Group for Science and Engineering (PAGSE) at Parliament’s Centre Block.
In his presentation, The Shale Gas Bonanza: Opportunities and Challenges, Lavoie confirmed fracking operations in British Columbia and Alberta have been “known to cause small seismic events.”
Hydraulic fracturing or fracking to access unconventional sources of natural gas like shale gas involves digging underground wells 200 to 3,000 meters vertically and another 1,000 meters or more horizontally to penetrate the rock-like shale.
Pressurized water mixed with hundreds of toxic substances (including hydrochloric acid, mercury and formaldehyde) is shot down the well to break apart the shale and push the natural gas to the surface.
A single fracking well consumes anywhere between seven to twenty-three million litres of water.
Lavoie believes the vast quantities of water industry injects into the ground is the “most likely candidate” for increasing the frequency and intensity of earthquakes in areas near fracking wells.
To demonstrate his point, Lavoie used fracking projects in northeastern B.C.’s Horn River Basin as his case study.
As long as monthly water injections at fracking wells remained around 100,000 cubic meters in the Horn River Basin, seismic activity did not increase beyond a magnitude of three. By 2010, as more fracking wells came online, water usage hit one million cubic meters— and earthquakes regularly went beyond magnitude three, peaking at 3.6.
When asked by Alberta MP Leon Benoit whether this seismic activity was problematic, Lavoie said earthquakes connected to Canadian fracking operations have not reached a magnitude yet where they could cause damage on the surface. Magnitudes of five and upwards can cause damage, according to Lavoie.
Fracking's environmental impacts: short on data
Five thousand trillion cubic feet of natural gas are locked in shale in Canada, most of which is in the Western Canada Sedimentary Basin. Not all of it is recoverable. Canada currently averages a twenty to twenty-five per cent recovery rate. If public opposition against fracking continues to grow, this recovery rate could drop even further.
“Assessing the environmental challenges to development is prerequisite to the social license,” Lavoie said.
Many of the other pressing “environmental challenges” that have come to light through a decade of fracking in B.C. and Alberta were not addressed in detail during the presentation.
Lavoie did state there was a definite need to collect baseline data before shale gas development takes place, echoing the findings of the Council of Canadian Academies (CCA) in 2014:
"There is reason to believe that shale gas development poses a risk to water resources, but the extent of that risk, and whether substantial damage has already occurred, cannot be assessed because of a lack of scientific data and understanding," the report concluded. The report was commissioned and released by Environment Canada on May 1, 2014.
B.C. only has 10 monitoring stations overseeing the operations of thousands of fracking wells.
Source: vancouverobserver.com/
Author: Derek Leahy
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