PITTSBURGH
(AP)—A new study being done by the Department of Energy may provide
some of the first solid answers to a controversial question: Can gas
drilling fluids migrate and pose a threat to drinking water?
A
drilling company in southwestern Pennsylvania is giving researchers
access to a commercial drilling site, said Richard Hammack, a spokesman
for the National Energy Technology Laboratory in Pittsburgh.
The
firm let scientists conduct baseline tests, allowed tracing elements to
be added to hydraulic fracturing fluids and agreed to allow follow-up
monitoring. That should let scientists see whether the drilling fluids
move upwards or sideways from the Marcellus Shale, which is 8,100 feet
deep at that spot.
“It’s like the perfect laboratory,” Hammack said.
Hammack said he believes this is the first time such research has been done on a commercial gas well.
“Conceptually,
it sounds like a really great idea,” said P. Lee Ferguson, a Duke
University civil and environmental engineering professor who is not
involved with the project. “I have wondered about this since I started
thinking about fracking. Which compounds are mobile and which aren’t?”
The
Marcellus Shale is a gas-rich rock formation thousands of feet under
large parts of Pennsylvania, New York, Ohio and West Virginia. Over the
past five years, advances in drilling technology made the gas
accessible, leading to a boom in production, jobs, and profits—and
concerns about pollution.
The
gas is pulled from the ground through a process called hydraulic
fracturing, or fracking, in which large volumes of water, plus sand and
chemicals, are injected deep underground to break shale apart and free
the gas.
Environmentalists
have claimed the fluids associated with drilling could rise and pollute
shallow drinking water aquifers. The industry and many government
officials say the practice is safe when done properly, but there have
also been cases where faulty wells did cause pollution.
Ferguson cautioned that no single study will answer all questions about fracking and the potential for pollution.
“The
complicating factor is some of the compounds don’t act in the same way
underground,” he said of fracking fluids, as well as the fact that there
are substantial differences in geology throughout the Marcellus region.
Hammack
said the study is designed to see whether the fracking fluids or
naturally occurring salty brine from deep underground reach a testing
area located at about 4,000 feet.
“We’re just looking for any indication of communication between the two zones,” he said.
If
the fluids do rise, more research will be needed, he said. If they
don’t reach the 4,000-foot level, there will be no need to test drinking
water aquifers, which are closer to the surface.
Other
researchers have asked the same question, but have done so using
computer simulations or testing not involving commercial wells. Both
methods mean there’s considerable uncertainty about the accuracy of the
projections.
For
example, a study released by other Duke researchers this week suggested
that deep, salty brine fluids could migrate upwards through natural
pathways, but made no estimate of whether that might take years, decades
or centuries.
Hammack said the new project took off after he told someone in the industry about research DOE hoped to conduct.
“They said, ‘We have that exact situation,'” Hammock said of the response from the firm, which he didn’t identify.
Hammack
said the monitoring will go on for at least a year, but that the
department will release information earlier if there’s proof the fluids
migrate to the upper testing level. Some background data from the
research is also expected to be available later this year.
Patrick
Creighton, a spokesman for the industry’s Marcellus Shale Coalition,
said in a statement that the industry supports partnering with
universities, government agencies and others to protect the environment.
Source: The Associated Press
