WILLISTON, N.D. (AP) -- The site where an underground pipeline leaked 1 million gallons of saltwater into the North Dakota badlands earlier this month could take years to clean up, an official of Native American tribes involved in the cleanup said Monday.
"One of the timelines I've heard — and I haven't been able to verify it yet — we're expecting at least three years," said Claryca Mandan, the head of the Mandan, Hidatsa and Arikara Nation Natural Resources Department.
Crestwood Midstream Partners LP discovered the saltwater spill from a pipeline near the town of Mandaree on July 8. The saltwater took a snaking, 8,420-foot path down into a ravine, but the company says there is no evidence it reached Lake Sakakawea, a source of drinking water for Fort Berthold Indian Reservation. Beaver dams were credited with helping contain the leak. Crestwood believes the spill — from a pipeline owned by Crestwood subsidiary Arrow Pipeline, LLC — started over the July 4 weekend.
Also called brine, saltwater is a byproduct of oil production that can be 30 times saltier than seawater. It is considered an environmental hazard.
The incident is one of the largest oil field spills in North Dakota history and is leading the Three Affiliated Tribes to review their pipeline regulations.
"It's caused us to rethink some of the pipeline standards that we have in those areas and we may be instituting some changes soon in the pipeline construction requirements," she said.
Mandan said that while the impact of the spill on wildlife has been minimal — with beavers and snapping turtles returning to the ravine — it continues to impact vegetation.
"I think there's also going to be some secondary contamination because of the root systems of the trees," said Mandan. "We're still noticing some die off going on in the trees, in vegetation higher up around the area of the dam."
So far, the area has been flushed with 29,000 gallons of water, she said.
But cleaning up saltwater spills can be a long, difficult process.
The Mandaree spill rivals a 2006 incident that sent more than 1 million gallons of saltwater into a creek, aquifer and pond near the tiny town of Alexander. Cleanup efforts are still ongoing at that site, which has been called the worst environmental disaster in state history, said North Dakota Water Quality Director Karl Rockerman.
Kris Roberts, an environmental geologist with the North Dakota Department of Health, said more than 10 million gallons of contaminated water have been recovered from that location to date.
The size and affected areas — and cleanup requirements — of a saltwater spill are usually no more than a best guess early on, Rockerman said.
"In our experience, they are more complex than they appear at first," he said.