CANNON BALL, N.D.-A status report from the contested Dakota Access Pipeline says it has completed the pilot hole for its horizontal drill under the Missouri River and the pipeline will be ready to flow oil as early as March 6.

The company filed the information in U.S. District Court in Washington, D.C., to comply with a federal court order for weekly updates on the pipeline's status while litigation with the Standing Rock and Cheyenne River Sioux tribes continues.

The first status report, filed Monday, says the pilot hole that stretches 7,500 feet from one side of the Missouri River/Lake Oahe just north of Standing Rock is being reamed to accept the 30-inch-diameter pipe.

Even as the $3.8 billion pipeline from North Dakota's Bakken oil fields to Illinois nears completion, the pipeline's future is in question in federal court. The tribes' attorney, Jan Hasselman, said he was surprised by the early oil-flow date, since the company told the court its best-case scenario was further out, into May.

Hasselman, on behalf of the tribes, wants Judge James E. Boasberg to issue a summary judgement in the case filed against the U.S. Army Corps of Engineers after it issued a general permit for the pipeline crossing in July.

Newsletter signup for email alerts

"We moved fast to get in front of operations. What's disappointing is that this (flow date) is a couple of weeks earlier than it told the court was its best-case scenario," Hasselman said. "Time is of the essence, but, as the judge said, the lawsuit doesn't become irrelevant if they turn on the tap, because he can always direct them to turn it off."

The case had been put on hold with the Obama administration' s decision to withhold the corps' river-crossing easement for the pipeline pending a full environmental impact statement, including whether tribal rights had been considered.

Then, the Trump administration reversed that decision and the Army issued an easement Feb. 7. That flip-flop put the case back on the front burner.

The tribe's motion for a summary judgement asks the judge to look at whether the pipeline easement violates the corps' duties under tribal law, the National Environmental Protection Act and the Clean Water Act.

In the past weeks, the Great Plains Tribal Chairman's Association, the Oglala Sioux, the Association of American Indian Affairs, the Pueblo of Pojoaque and the National Indian Women's Resource Center have joined the suit.

Hasselman said the case - with its emphasis on tribal treaty rights, specific to lands around the reservation and Lake Oahe - will cause the court to take up new questions and get to the very heart of the legality of the easement.

The corps has not yet filed a response to the motion for summary judgement.

On Tuesday, Boasberg will hear the Cheyenne River's request for a preliminary injunction against the pipeline on grounds that it interferes with the tribes' right to practice its religious freedoms with pure water. He denied a temporary restraining order on those grounds two weeks ago.

The pipeline company says this belated claim is too late and that, as a private company, it has no legal duties under the Religious Freedom Restoration Act.

Dakota Access is drilling the pipe about 100 feet below the river bed thtough intermittent clay, sand and silt, according to the construction map filed with the State Water Commission. The pipe is coated with 14 to 16 mils of epoxy and 40 mils of abrasion resistant overlay.