Study indicates lingering saltwater contamination in oil patch

by Lauren Donovan, originally posted on April 27, 2016


A published and peer-reviewed Duke University study finds that thousands of saltwater and frack flowback spills throughout the oil patch have left a legacy of toxic contamination, including radioactive soils and polluted streams unsafe for human consumption and aquatic health.

The Duke team of researchers, which advocated that more study is needed, published the findings Wednesday in the Environmental Science & Technology journal. Funding for the project came from the National Science Foundation and the Natural Resources Defense Council.

A North Dakota health official said the study only looked at spills still being remediated, not sites that have been cleaned up.

Avner Vengosh, professor of geochemistry and water quality at Duke, said the magnitude of 9,700 new wells drilled over the decade in North Dakota is the reason why the contamination is so widespread, compared to other regions.

“This massive development has led to more than 3,900 brine spills, mostly coming from faulty pipes built to transport fracked wells’ flowback water,” said Vengosh, adding that his researchers have been studying frack-related science for six years across the country and the magnitude of spills is unprecedented.

“It’s a phenomenon we’ve never seen before,” he said.

A lead study author, Nancy Lauer, said the metals and salts in the brine spills don’t break down in soil, unlike oil.

“This has created a legacy of radioactivity at spill sites,” she said.

The State Health Department’s environmental chief David Glatt said findings that brine water spills are highly mineralized is no surprise and the department’s always maintained it would rather deal with spilled oil than produced water.

That said, he says the study looks at three spill sites that are still being remediated and one legacy spill at an injection well that he says needs to be addressed, but doesn’t look at spill sites that have been cleaned by removing contaminated soil and flushing with fresh water. One of the sites, near Bottineau, has been in remediation for four years; another for two, he said.

“To say the whole Bakken is a concern, that’s a stretch. The vast majority of spills have been cleaned up and (the contaminants) are a lot closer to (normal) background levels,” Glatt said. “I wish we would have been contacted. We’ve done a lot of things and a lot of follow up to make sure companies get right on it. The vast majority don’t become a problem.”

In an interview with the Tribune, Vengosh said the study is based on hard data and objective science and that state health and oil officials shouldn’t be surprised by the outcome.

“Didn’t they think this would be?” he said.

Dakota Resource Council members agreed their land, impacted by the spills, could be used for the study. DRC organizer Nicole Donaghy, if it’s truly a question of “remediated” versus “unremediated” sites, “We’d be happy to submit samples of fully remediated sites at saltwater spills.”

The study mapped the 3,900 recorded spills and involved complex measurements from four spills — two major, two minor — that occurred over the past four years in the Bakken and Bottineau fields. Vengosh said the study didn’t go wide across spills, but deep into characteristic ones. The samples were taken to the lab to identify specific isotopes for “fingerprints” or “tracers” to distinguish them in soil and water.

He said the study should be a wakeup call, because the persistent presence of the toxins, even four years after a spill, means there’s been no effective cleanup.

“There needs to be much more monitoring and evaluation to protect drinking water. North Dakota needs to address this and take steps to avoid it,” he said.

Alison Ritter, spokeswoman for the state’s Oil and Gas Division, said an analysis of spills and brine water pipelines led to new rules to expand the division’s jurisdiction. Those rules, still in the proposal stage, require bonding, more inspection and enforcement and prior notice of pipeline installation. She said the department also wants to increase diking requirements so spills are better contained.

“Remedies to the issues raised in the study have been in the works since the 2015 Legislature,” said Ritter, adding that the state is looking at implementation in October.

The study authors conclude that the resistance of contamination to biodegradation and its persistence in the environment “suggest that contamination from brine spills in North Dakota will continue to impact nearby water resources for years to come.”

More study is recommended, and Vengosh said his team plans to follow up work in North Dakota.

Darrell Dorgan, chairman of the North Dakota Energy Industry Waste Coalition, said the study is no surprise to anyone who has followed the state’s failure to regulate the oil industry.

He said the study makes new health department rules to allow disposal of radioactive waste even more alarming.

“If people think this study points to a building tragedy, just wait. The new rules allow radioactive waste that is 10 times more dangerous,” Dorgan said.

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