In this Oct. 5, 2016, file photo, heavy equipment is seen at a site where sections of the Dakota Access pipeline were being buried near the town of St. Anthony in Morton County, N.D. Native American tribes opposed to the Dakota Access Pipeline once again have asked a federal judge to stop the flow of oil while the legal battle over the line’s future plays out. (Tom Stromme/The Bismarck Tribune via AP, File)

BISMARCK, N.D. (AP) — Native American tribes opposed to the Dakota Access Pipeline once again have asked a federal judge to stop the flow of oil while the legal battle over the line’s future plays out.

The Standing Rock Sioux and other tribes succeeded on their first attempt, only to have an appeals court overturn U.S. District Judge James Boasberg’s shutdown order earlier this year. Now, the Bismarck Tribune reports, they’re asking the judge to clarify his shutdown ruling from this summer to satisfy the appellate judges and then to again order the line to cease operations.

Pipeline operator Energy Transfer and the Army Corps of Engineers both maintain the pipeline is safe. They have have until Nov. 20 to file a formal response.