Study: Treated Oil, Gas Wastewater Leaves Radioactive Contamination
By: Dan Heyman, Public News Service – WV
CHARLESTON, W.Va. — Over time, treated oil and gas wastewater is leaving radioactive deposits in the stream beds where it is released, scientists have found.
A team of Duke University researchers found highly elevated levels of radium in the mud where three Pennsylvania treatment plants released wastewater. That’s even after the water was treated to greatly reduce its radioactivity, said Avner Vengosh, the professor of geochemistry who led the research team.
“We found that, indeed, there is a large enrichment of radioactive elements in those stream sediments,” Vengosh said. “It’s about 600 times the level that we found upstream.”
The industry says the brine and other water from oil and gas wells contains some naturally occurring radioactive elements, but only at very low levels. Vengosh and his team have been focusing on the ways these elements become concentrated in stream beds.
Vengosh noted the treated wastewater was from conventional oil and gas wells, not fracking wells – although he said the Duke researchers have found similar issues where fracking wastewater had been released. He added that Pennsylvania stopped the release of treated wastewater from fracking operations some years ago.
He said one troubling issue is how high these concentrations can get – as high as ten times the radioactivity of low level radioactive waste from, say, a hospital or power plant.
“So they are exceeding the level that this site should be, defined as a low radioactive disposal site,” Vengosh said. “Obviously, they are not – it’s the middle of a stream in Pennsylvania.”
He said most of the nation’s oil and gas brine is injected into deep disposal wells, although the geology in Pennsylvania often makes that impossible. Vengosh said treating the wastewater isn’t enough.
“I don’t think there is a direct human health risk immediately from those sites,” he said. “But there is a chronic contamination of the environment. Even the treatment, it’s not sufficient to address this problem.”
Oil and gas wastewater is sometimes used to melt the ice on roads. Vengosh said that also may not be safe.
