The Trump administration is giving final approval for the Dakota Access Pipeline

This is it: The Trump administration is about to approve the final permit needed to finish the Dakota Access Pipeline, US Army officials told Congress on Tuesday.

While it’s still possible that a last-minute legal challenge could halt the controversial project, the pipeline is now very, very close to completion. Once built, it would transport 450,000 barrels of crude oil per day from the Bakken fields of North Dakota to a shipping terminal in Illinois.

The pipeline is currently about 85 percent finished, save for a section that would pass under Lake Oahe on the Missouri River — a reservoir that serves as the main source of drinking water for the nearby Standing Rock Reservation. For months, the Standing Rock Sioux and various activists have protested the pipeline’s construction, arguing (among other things) that the tribe wasn’t properly consulted on the pipeline and that a leak could endanger vital water supplies.

Because the land around Lake Oahe is owned by the Army Corps of Engineers, the agency has final say for this part. And in late 2016, after prodding by the Obama administration, the Army Corps announced it would consider alternative routes for the pipeline — a process that would require a lengthy environmental review.

But then Donald Trump entered the White House and, in one of his first actions, ordered the Army Corps to “take all actions necessary and appropriate” to review and approve the pipeline “in an expedited manner.” He wanted the pipeline built — and fast.

In response, the Army Corps now says it will skip that whole environmental review — even though it had already started — and will just grant the easement at Lake Oahe needed to finish the project within 24 hours. The company behind the pipeline, Energy Transfer Partners, told Reuters that construction would begin quickly. Within 90 days, the pipeline would be fully operational.

Jan Hasselman, an attorney with Earthjustice who represents the Standing Rock Sioux, says via email that the tribe will challenge the Army’s decision in court: “The Obama administration correctly found that the Tribe’s treaty rights needed to be respected, and that the easement should not be granted without further review and consideration of alternative crossing locations. Trump’s reversal of that decision continues a historic pattern of broken promises to Indian Tribes and violation of Treaty rights. They will be held accountable in court.”

But blocking construction looks like a long shot at this point. Back on September 9, a federal judge rejected the tribe’s request for an injunction to halt the pipeline while the DC Circuit Court heard a broader case over whether the Army Corps properly consulted the Standing Rock Sioux. (That case is still ongoing.) So the tribe would have to come back and ask yet again for an injunction — this time over the fact that the Army Corps decided to ignore an ongoing environmental review. It’s unclear if the judge would be any more sympathetic this time around.

In the meantime, there are still a few hundred protestors left in the areas around the Standing Rock Reservation who have stayed through the harsh winter. Tribal officials have been trying to convince people to leave so that they can clean the site before the spring flooding starts. The federal government, for its part, has begun sending in law enforcement agents to disperse the remaining protestors.

— Here’s our full explainer on the battle over the Dakota Access Pipeline, which will take you through November, just before the Army Corps decided to consider alternate routes.

— More relevant background: “The companies behind the Dakota Access pipeline have reported thousands of gallons of oil spilled in dozens of industrial accidents over the last two years, according to an analysis performed by anti-pipeline environmental groups.”