The Department of Energy’s National Energy Technology Laboratory (NETL) in Pittsburgh is tackling the thorny question raised by Duke University earlier this week: Can and does fracking fluid (or any fluid) migrate upward through rock layers? The Duke study released earlier this week suggests it’s possible for fluids to migrate from thousands of feet down (see this MDN story) up to water aquifers near the surface. News of the Duke study continues to reverberate throughout the media with hundreds of stories being written and endlessly recycled.
The NETL will tackle the same question using an active, commercially drilled Marcellus Shale natural gas well in southwestern Pennsylvania. Using a single well won’t provide definitive answers because Marcellus geography varies from region to region—but at least it’s a start. Recall that the Duke study focused on data from six northeastern Pennsylvania counties and their data did not include sampling from active drilling sites.
The unnamed driller cooperating with NETL has already allowed them access to the site to conduct baseline sampling. The NETL has also injected tracer chemicals that will allow them to track the fracking fluid. The NETL wants to see if the fluid migrates from 8,100 feet—the depth of the existing Marcellus well—up to the 4,000-foot level. If it does, more testing will be done. If it doesn’t migrate that far, the question is answered—at least for that location—and no further testing is required.
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.
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.
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.*
*Wheeling (WV) The Intelligencer/Wheeling News-Register (Jul 12, 2012) – Federal Lab Using Drilling Site For Study of Fracking Liquids