BILLINGS, Mont. — U.S. prosecutors suspect a Wyoming company may have covered up problems with a pipeline that ruptured in 2015 and spilled more than 50,000 gallons (240,000 liters) of crude into Montana’s Yellowstone River, clogging the river. drinking water supply to a small town, according to court documents.
The government is suing Bridger Pipeline for violating environmental laws in the 2015 spill, which occurred after the pipe buried under the Yellowstone was exposed and broke when ice eroded the bottom of the river near Glendive, Montana .
The accident happened a few years after an Exxon-Mobil pipeline spilled into the river near Billings. The spills helped put a spotlight on the nation’s aging pipeline network, which has continued to suffer high-profile accidents, including recent spills in Louisiana and California.
An investigation of Bridger’s pipeline for the company in 2011 included a note that the pipe was buried just 1.5 feet (0.5 meters) below the ever-changing river bottom. This would have put him at an increased risk of rupture.
But after the spill, prosecutors say, company officials referred to a second investigation when they told federal regulators the pipeline had been buried at least 7.9 feet (2.4 meters), him giving “adequate coverage” to protect against spills.
“This raises questions — which Bridger has yet to answer — about whether Bridger hid material facts about the condition of the crossing prior to the Yellowstone spill,” Assistant U.S. Attorney Mark Elmer wrote. in court documents.
Bridger’s attorneys have dismissed claims of conflicting investigations as “conspiracy theories.”
Pipeline company spokesman Bill Salvin said the government misunderstood the polls.
“There was adequate depth of cover the entire traverse,” Salvin said. “We think the government is trying to find something that just doesn’t exist.”
Federal prosecutors are pursuing a separate case against sister company Belle Fourche Pipeline over a 2016 spill in North Dakota that released more than 600,000 gallons (2.7 million liters) of crude and contaminated the Little Missouri River and a tributary.
Both pipeline businesses are part of True Companies, based in Casper, Wyoming, which operates 1,800 miles (2,900 kilometers) of lines in Montana, North Dakota and Wyoming.
Prosecutors allege the spills violated the Clean Water Act and are subject to fines of up to $6.6 million in the Montana case and up to $89.5 million in the Dakota case North.
Salvin declined to comment on the North Dakota case. Thursday is the deadline for the company to respond to the government’s allegations, under an order from U.S. Magistrate Judge Clare R. Hochhalter.
The legal challenges over the spills come as Bridger seeks to build a new pipeline from western North Dakota to southeast Montana. The North Dakota Public Service Commission approved part of the line last month.
Bridger reached a $2 million settlement with the federal government and Montana last year over damages from the Yellowstone River spill. The company had previously been fined $1 million in the case by the Montana Department of Environmental Quality.
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