BISMARCK, N.D. (AP) — Earthen barriers have been set up across a creek and water was being tested Thursday around the site of a nearly 3 million-gallon leak of saltwater generated by oil drilling, the largest spill of its kind during North Dakota's current oil rush.
The berms were built at Blacktail Creek to prevent potentially contaminated water from flowing out of the creek and into a bigger body of water that eventually leads into the Missouri River.
"So when the ice starts to melt if there's any oil or contaminated water, they can contain it and pump that out before it goes downstream," said Dave Glatt, chief of the North Dakota Department of Health's environmental health section.
Pipeline operator Summit Midstream Partners LLC and state inspectors will keep testing the soil and water at the Blacktail Creek and larger Little Muddy Creek until after the ice melts this spring, Glatt said.
Saltwater, known as brine, is an unwanted byproduct of oil and natural gas production that is much saltier than sea water and may also contain petroleum and residue from hydraulic fracturing operations. Some previous saltwater spills have taken years to clean up.
The spill was detected Jan. 6 during a periodic inspection by the company, which said Thursday the cause of the rupture in the pipeline and when exactly it happened is still unknown. The portion of the pipeline that ruptured has been sent to a laboratory to be analyzed, and Summit Midstream said crews are probing the soils and water close to the rupture to determine the ultimate cause and extent.
Summit Midstream has said that as crews "actively investigate the cause of the spill," it is focused on minimizing and fixing any environmental impacts.
Glatt said crews hired by Summit Midstream are still at the site, vacuuming any contaminated water that reaches Blacktail Creek as ice melts. About 65,000 barrels of a mix of fresh water and saltwater already have been pumped out of the creek. That water is being taken to wells where it is being injected into the ground.
Saltwater is usually pumped underground for permanent storage from a network of saltwater pipelines that extends to hundreds of disposal wells in the western part of the state.
The latest spill is almost three times larger than one that fouled a portion of the Fort Berthold Indian Reservation in July. Another million-gallon saltwater spill in 2006, near Alexander, is still being cleaned up nearly a decade later.
"This saltwater stuff is devastating to the land," said Don Morrison, executive director of the Dakota Resource Council, an environmental-minded landowner group. "When this stuff gets on a farmer's field, nothing can grow. This isn't like the stuff from the ocean — it's also full of chemicals."
Glatt has said a handful of farmers have been asked to keep their livestock away from the two creeks.
Morrison said his group's membership had grown by about a third in the past year, due in part to the growing number of saltwater spills in the state.
"Thousands of acres are already destroyed in North Dakota because of this and thousands more will be destroyed with this recent spill," Morrison said, calling for action by state officials.
Democrats in North Dakota's legislature said Thursday they will revisit measures proposed by a Republican and overwhelmingly rejected two years ago that would require flow meters and cutoff switches on pipelines that carry oilfield wastewater.
House Assistant Minority leader Cory Mock, D-Grand Forks, told The Associated Press the legislation is expected to be introduced by Monday.
Alison Ritter, a spokeswoman for the state Department of Mineral Resources, whose agency regulates North Dakota's oil and gas industry, said the pipeline that breached near Williston had some "metering" in place but it is not known what type. Glatt said the metering was installed around Christmas.
Garcia Cano reported from Sioux Falls, South Dakota.
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