Dangerous levels of radioactive materials from unconventional oil and gas extraction have accumulated in a Pennsylvania stream, which is currently in the process of being cleaned up.
Radium-226 (half-life of 1,601 years) and radium-228 (half-life of 5.75 years) were found in the sediment of Blacklick Creek in Indiana County, where the Josephine Brine Treatment Facility discharges its effluents. The radioisotopes were present at levels above safe limits.
The results were presented in a peer-reviewed study published yesterday in Environmental Science & Technology. The work was done by the same Duke University team that has previously found methane in groundwater near hydraulic fracturing sites. It was funded by the Park Foundation, a nonprofit that often funds anti-fracking activists. The researchers said the foundation did not have any control over the study or results.
Radioactivity is a concern of residents who have seen a rise in unconventional oil and gas generation. Radium is a naturally occurring element, and it rises to the surface during oil and gas drilling together with brine.
The researchers do not know whether the contamination is limited to Josephine facility or could be present near similar wastewater treatment plants in the state.
"Is this a problem that just this facility wasn't treating [the brine] adequately, or do all facilities share the same common discharge?" asked Nathaniel Warner, a researcher at Dartmouth College who did the work while at Duke. "I woud imagine that other facilities do similar methods, so some of the larger operators would have similar results."
Documents provided by the Pennsylvania Department of Environmental Protection suggest this may indeed be the case.
The DEP and U.S. EPA have been aware of the contamination near the Josephine facility since at least July 2011, when the agency tested the sediments at Blacklick Creek and found radioactivity higher than the base line established by EPA.
The DEP asked Fluid Recovery Services LLC, the company that runs Josephine and two other wastewater treatment facilities, to test for contamination in the fall of 2012. The company found high levels of radioactivity near its facilities.
The contaminated waters included Blacklick and the Allegheny River downstream of the Franklin treatment facility in Venango County. Tests were inconclusive at the McKee Run downstream of the Creekside treatment facility in Indiana County.
The company settled with EPA, paying $83,000 for Clean Water Act violations in May this year (EnergyWire, May 23). And the DEP asked Fluid Recovery Services to clean up the streambeds in a consent order issued at the same time.
Fish and other water creatures can ingest the radium in the water, where the element accumulates in tissues and begins to wreak havoc. Atoms of radium contain a nucleus with an unequal number of neutrons and protons, which makes the element unstable and highly energetic. In an effort to gain stability, the nucleus spits out particles that can damage the genetic material of whichever organism the material is within.
The Marcellus Shale Coalition, an industry group, stressed that industry no longer uses wastewater treatment facilities to dispose their wastes.
“It is unfortunate that the researchers and funders of this study either did not know or would not acknowledge that the shale industry has not taken flow-back water to this treatment facility, or any similar facility in Pennsylvania, since May 2011, which underscores the outdated nature of the data used for the report," said Patrick Creighton, an MSC spokesman.
Most operators in Pennsylvania today dispose of brine by injecting it underground at deep injection sites. But in 2010, they were predominantly sending the wastewaters to brine treatment facilities such as Josephine. The facilities would remove the salts, heavy metals and most other contaminants from the water and send the solid sludge (also high in radium) to landfills. The facilities would discharge the effluents into creeks and rivers.
The Josephine facility received unconventional oil and gas wastes until September 2011, according to the DEP.
The Josephine facility had the ability to remove 90 to 95 percent of the radium present in brine, Warner said. So a minuscule amount of radium was getting discharged into the creek, which began collecting in the streambed.
The Duke scientists collected water samples between August 2010 and November 2012 at Blacklick Creek and analyzed the samples for a variety of chemicals including sodium, barium, strontium, and of course radium-226 and radium-228.
They found radioactivity levels as high as 200 times the background level.
The ratio of radium-226 to radium-228 in the streambed had a signature as unique as a thumbprint: The contaminants originated in the Marcellus Shale.
More than three years since the contamination was found by regulators, Fluid Recovery Services is just beginning to remediate the Blacklick Creek and the Allegheny River sites.
Part of the reason for the delay may be the DEP's determination, in its consent order, that the radioactivity, though above background levels, did not pose a risk to anyone passing by the stream or to workers.
Warner and his colleagues, however, note in their study that someone should look at bioaccumulation of these elements in aquatic life. It is also unclear whether similar contamination has been found at other wastewater treatment plants.
"I wonder if DEP has looked at the sediments at even more facilities and found similar results," Warner said.
This article was updated to include comment from the Marcellus Shale Coalition.