BISMARCK, N.D. — It probably will take until next spring for the Army Corps of Engineers to finish court-ordered additional environmental study of the Dakota Access oil pipeline, agency attorneys said in court documents filed Friday.

The Corps had anticipated completing the task by the end of the year, but Justice Department attorney Matthew Marinelli said it will take longer than expected to get needed information including spill modeling from Texas-based pipeline developer Energy Transfer Partners and possibly from at least one unspecified American Indian tribe.

“Given the current expected time frame for the receipt of additional information, the Corps now anticipates that its review and analysis … will not conclude until approximately April 2, 2018,” Marinelli wrote.

The $3.8 billion pipeline began carrying oil from North Dakota through South Dakota and Iowa to a distribution point in Illinois on June 1. However, four Sioux tribes in the Dakotas continue challenging it in federal court in Washington, D.C., because they fear a leak could contaminate their water supply. The pipeline crosses beneath the Lake Oahe reservoir on the Missouri River just to the north of the Standing Rock Reservation that straddles the North Dakota-South Dakota border.

“The notice says they are conducting additional oil spill modeling β€”in other words, this wasn’t done before the Trump administration approved (the pipeline),” tribal Chairman Dave Archambault said Friday in a statement to The Associated Press. “This confirms what we’ve been saying from the start β€” until there’s been a full analysis of risks and impacts to the Standing Rock tribe, the pipeline should be shut down.”

U.S. District Judge James Boasberg is considering halting pipeline operations while the additional study is done. It’s not known when he’ll rule.

Boasberg ruled on June 14 that the Corps largely complied with environmental law in giving its permission for the pipeline project, but that it didn’t adequately consider how an oil spill under Lake Oahe might affect the Standing Rock tribe. He also said the Corps didn’t adequately study how the pipeline might disproportionately affect the tribal community β€” a concept known as environmental justice. That aims to ensure development projects aren’t built in areas where minority populations might not have the resources to defend their rights. Boasberg ordered the Corps to reconsider those issues.

The Corps is “actively working on ways to shorten” the new April timeline for completing the work, Marinelli said.


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