Separating fracking from aquifers can eliminate water risk: study
London (Platts)--25Apr2012/533 am EDT/933 GMT
Stopping oil and gas companies from fracking shale rocks within 600
meters of aquifers could virtually eliminate any risk of drilling operations
leading to contamination of drinking water, according to a new study led by
scientists from the UK's Durham University.
The study, based on available data from thousands of fracking operations
in the US and natural rock fractures in Europe and Africa, found that the
probability of rogue fractures caused by fracking extending beyond 600 meters
was "exceptionally low."
The chance of fractures extending for more than 350 meters was found to
be around 1%, according to the study.
"Our research found contamination of aquifers from drilling is very,
very unlikely," Professor Richard Davies of Durham University told Platts,
adding that the argument that oil and gas fracking could lead to water
contamination was "probably a bit of red herring."
Article continues below...
Sign up to Oilgram News today.
Oilgram News brings fast-breaking global petroleum and gas news to your desktop every day. Our extensive global network of correspondents report on supply and demand trends, corporate news, government actions, exploration, technology, and much more.
Oil and gas fracking is only at a very early stage in Europe, and in
some countries has faced considerable opposition over its potential
Fracking, or hydraulic fracturing, uses water and other chemicals to
widen fractures in shale rock and recover trapped oil and gas. Opponents fear
that this could lead to the hydrocarbons or the chemicals involved in
fracking leaking into shallower drinking water aquifers.
Davies said regulators should consider imposing a minimum vertical
distance below aquifers for fracking operations, and that this distance
should probably be greater than 600 meters.
"600 meters is probably a starting point but in a new area you'd
probably want to be a lot further away. As new rocks are explored ... we're
going to have to be very cautious," he said.
The study, titled "Hydraulic fractures: How far can they go?", was
conducted by scientists from Durham, Cardiff University in Wales and the
University of Tromso in Norway.
As well as studying natural rock fractures offshore Norway, Mauritania
and Namibia, the research drew on data from operations in the Eagle Ford,
Woodford, Barnett, Marcellus and Niobrara shale areas in the US.
In almost all these cases the fracking was occurring at depths below
ground of 1,000-4,000 meters, Davies said, with the exception of some
drilling at Pavillion in Wyoming, which has become the subject of a
controversial groundwater review by the US Environmental Protection Agency.
--Richard Swann, firstname.lastname@example.org