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Manmade earthquakes trigger government drill-down

May 9, 2012  By The Canadian Press


April 18, 2012, Vancouver – A booming gas extraction process that has environmentalists all
shaken up is being probed by two different studies to determine if it's
also causing the depths of Canada to rattle and roll.

April 18, 2012, Vancouver – A booming gas extraction process that has environmentalists all
shaken up is being probed by two different studies to determine if it's
also causing the depths of Canada to rattle and roll.

The research into whether hydraulic fracturing, or
fracking, can trigger earthquakes is being conducted just as a pair of
independent papers were released internationally this week suggesting
they do.

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The studies out of mid-continent U.S. and Britain found that
shallow, man-made tremors may be linked to the blasting of water, sand
and chemicals deep underground to break open rock to obtain crude oil
and natural gas.

Experts and critics alike are waiting for conclusive
results from home soil before suggesting industry practices should be
altered.

"These are tiny earthquakes and they're the variety that
occur thousands of times a day around the world," said John Cassidy, a
federal government seismologist in Victoria, B.C., of the international
findings.

He said mounting interest and unusual vibrations in British Columbia have prompted closer study at home.

"The idea is to be able to provide well-grounded science
advice that can be used by regulators across the country for their
decision-making."

A four-year study was launched by the federal Natural
Resources Department on April 1. With the aid of industry regulators and
universities, it will seek to unearth whether fracking has inducing
quakes in British Columbia, New Brunswick and Quebec, Cassidy said.

A provincial study is also underway in a region of
northeastern B.C. called the Horn River Basin, where at least 11 energy
companies are developing significant shale gas extraction projects. The
study, being conducted by the BC Oil and Gas Commission with commercial
co-operation, should be completed later this year.

"They've seen some seismic activity in that area … (It's)
definitely worth taking a look at," said Travis Davies, a spokesman for
the Alberta-based Canadian Association of Petroleum Producers, which
represents 90 per cent of the Canadian industry.

"If you want to have a licence to operate and be on the
land, you need to have public support. The public needs to feel safe and
comfortable and that's why we support the (commission's) work."

The province's west coast already experiences about 2,000 natural quakes annually, Cassidy said.

Yet 36 earthquakes have occurred in the otherwise
seismically quiet region near Fort Nelson over the past three years.
Most hovered between magnitude two and three in scale, a class
considered minor but that could be felt as shaking by someone in the
close vicinity.

Fracking in that region occurs about 2.5 kilometres under
ground, around the same depth the natural tremors occur. Drinking water
wells are situated about 150 metres to 300 metres in depth.

B.C. Energy and Mines Minister Rich Coleman said Tuesday
the implications of the recent studies will be considered within the
province's own examination.

"This study will help ensure B.C. remains a leader in safe and responsible natural gas activities," he said in a statement.

A spokesman for the BC Oil and Gas Commission referred a request for comment back to the minister.

Two further reviews of the environmental impact of fracking
were announced in September by federal Environment Minister Peter Kent.
The ministry will conduct one assessment, while an independent panel
has been tasked with the other.

On Wednesday, the U.S. Geological Survey was set to release
at a conference in San Diego its own findings that a "remarkable"
increase of quakes in middle U.S. since 2001 is "almost certainly" the
result of oil and gas production.

The study says there's been a six-fold increase in seismic
events there over 20th century levels, and it appears to be related to
deep, waste-water injection wells.

"A naturally-occurring rate change of this magnitude is
unprecedented outside of volcanic settings or in the absence of a main
shock, of which there were neither in this region," the study abstract
says.

Its authors note that work remains to determine how the
quakes are related to methods of extraction or the rate of gas
production.

Experts in the U.K. have interpreted another study,
released on Monday, as showing that so long as regulations are
effectively implemented, the risk of induced quakes should not prevent
further hydraulic fracturing.

"They are of insufficient magnitude and extent to cause
structural damage or to allow gas or chemicals to leak into much
shallower drinking water aquifers," geosciences Prof. Andrew Aplin, of
Newcastle University, said in a statement.

The study, released by the British Geological Survey and
commissioned by a resources company, focused on a particular shale gas
fracturing operation in northwest England after a series of quakes there
one year ago. It found they occurred after fluid was injected into a
nearby fault zone.

Fracking is well established in B.C., Alberta and
Saskatchewan, and exploration is picking up pace in almost every other
province.

Opposition has also ramped up steadily since the release of
the 2010 Josh Fox documentary "Gasland," which shows residents of
small-town Colorado setting alight tap water they charge was soured by
local fracking.

Ben Parfitt, who has researched fracking for two years at
the Canadian Centre for Policy Alternatives, said concerns and questions
arise from the notion of manmade earthquakes.

"Generally speaking, the way in which fracking operations
are presented to the public … is that these are highly-controlled
operations," he said. "If you're inducing small earthquakes underground,
how able are you to determine what the outcome is?"

He fears the possibility of ground-water contamination or gas migration that could put public health and safety at risk.

A 1994 study in the Fort St. John area of B.C., prompted by
several small earthquakes in the preceding decade, showed that reducing
injection pressure when fracking could stem the tremors, Cassidy said.

"It was a study that benefited the community, because it
was understood what caused these small earthquakes … and it benefited
industry because they could do their work without causing these
earthquakes," he said. "It was a good win-win situation."


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