By BLAKE NICHOLSON
Associated Press

BISMARCK, N.D. (AP) - The four Native American tribes in the Dakotas that are fighting the Dakota Access oil pipeline in court are seeking to challenge the recent conclusion of federal officials that a spill would not greatly impact tribal populations.

The Standing Rock, Cheyenne River, Yankton and Oglala Sioux in recent weeks all have sought permission from a federal judge to contest the results of a study conducted by the Army Corps of Engineers.

The Corps recently made public a 140-page technical report detailing its work over more than a year. It says the pipeline doesn't pose a higher risk of adverse impacts to minority and poor people.

Judge James Boasberg is working with the parties to determine the best way to proceed. A status conference is scheduled Wednesday in Washington.

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