Fracking research done in Western Pennsylvania encourages scientists
Recent federal testing at a shale gas site in the region is encouraging and could help confirm how unlikely it is that deep-shale drilling's underground cracks cause well water contamination, several scientists said on Friday.
Department of Energy researchers spent a year using seismic monitors, tracer fluids and shallow bore holes to monitor a Marcellus shale drill site in Greene County. Preliminary results show no evidence that chemicals from hydraulic fracturing — the natural gas drilling process — traveled to within 5,000 feet of the surface, nearly a mile from aquifers, a geologist with the agency told The Associated Press.
The study won't rule out several other water risks expanded gas drilling poses, but it probably will help confirm long-held beliefs that shale formations more than a mile underground are too isolated for gas drilling fractures to make a path to the surface, several scientists said. The agency has a unique testing setup in Greene County and a history of reliable research, experts said.
“It's compelling,” said Aimee Curtright, a scientist for RAND Corp. in Oakland who has studied the impacts of gas drilling. “It doesn't surprise me that they don't see any problems because that is very unlikely. ... That doesn't necessarily mean there's not another mechanism for contamination.”
Hydraulic fracturing led to a gas drilling boom, sparking fears about the consequences of drilling a mile deep and cracking underground rock thousands of times. The state has blamed above-ground mistakes and poor well construction for hundreds of incidents that have polluted surface and groundwater, including 161 incidents that damaged drinking water that The Scranton Times-Tribune uncovered earlier this year.
The National Energy Technology Laboratory in South Park set out to test whether the underground cracks can lead to aquifer pollution. It partnered with an unnamed drilling company that controlled several old shallow wells above deep wells it planned to drill, Richard W. Hammack, a scientist overseeing the project, told the Tribune-Review last year.
Hammack and several other lab officials did not return phone calls for comment. The lab expects to finish a final report by year's end, said Shelley Martin, its spokeswoman in Morgantown, W.Va.
“We are still in the early stages of collecting, analyzing and validating data from this site,” she said. “While nothing of concern has been found thus far, the results are far too preliminary to make any firm claims.”
The few tests that have suggested fluid could go from deep layers to shallow layers had big flaws, researchers at West Virginia University said. Underground fluid moves a few feet every day, and impervious rock layers cap the Marcellus and Utica shales, making connections in a human's life unlikely, experts said.
But that means a test such as this one might never be conclusive, experts said. With only one site tested and one year of data, the test could miss pollution that travels later, or that would travel with different drilling in a different geology, said Joe Donovan, a geology professor at the university.
“It's a good experiment. It's safe,” Donovan said. “But these tracer tests are always a bit speculative. ... You have to wait and see if the fluids return, and you don't know when that's going to be. You could wait days, months or even years.”
The public deserves to have more independent research such as this, said Kathryn Klaber, president of the Marcellus Shale Coalition, a group that represents drillers. Her group is eager to see the full report from federal officials, she added.
“Our industry does a lot of analysis of how this work is done and has been confident that there's not that vertical migration,” Klaber said. “Any results confirming that is very good news for the industry.”
The public needs to realize, however, that this is just one small element of the natural gas boom, said Myron Arnowitt, state director of Clean Water Action.
The advance of hydraulic fracturing has led to thousands of new gas wells in Pennsylvania alone. That leads to risks from poorly constructed wells, leaky waste pits above ground and poorly managed sites, he said, echoing comments from scientists.
“There are so many ways that natural gas extraction can lead to contamination that looking at fracturing coming to the surface is maybe one of the least likely possibilities,” Arnowitt added.
Pennsylvania environmental regulators have “documented 161 cases of Marcellus wells causing water contamination, and I'm sure most of them are not from the kind of incident that (the Department of Energy) is looking for,” he said.
Timothy Puko is a staff writer for Trib Total Media. He can be reached at 412-320-7991 or firstname.lastname@example.org.