The Obama administration has denied a final approval for the Dakota Access pipeline.
The Army Corps of Engineers announced today that it would not issue an easement for the oil project to cross Lake Oahe, a dammed section of the Missouri River. Instead, the agency will undertake additional National Environmental Policy Act analysis to consider potential impacts and alternative routes.
"Although we have had continuing discussion and exchanges of new information with the Standing Rock Sioux and Dakota Access, it's clear that there's more work to do," Assistant Secretary of the Army for Civil Works Jo-Ellen Darcy, who oversees the Army Corps, said in a statement. "The best way to complete that work responsibly and expeditiously is to explore alternate routes for the pipeline crossing."
Interior Secretary Sally Jewell praised the news.
"The thoughtful approach established by the Army today ensures that there will be an in-depth evaluation of alternative routes for the pipeline and a closer look at potential impacts, as envisioned by NEPA," she said in a statement.
The Standing Rock Sioux Tribe, the group that led opposition to the project, which would cross within a half-mile of its reservation, was elated at the news today.
"We wholeheartedly support the decision of the administration and commend with the utmost gratitude the courage it took on the part of President Obama, the Army Corps, the Department of Justice and the Department of the Interior to take steps to correct the course of history and to do the right thing," Chairman Dave Archambault II said in a statement.
The easement was the final federal approval necessary for project backer Energy Transfer Partners LP to complete construction on the 1,170-mile pipeline, which would transport oil from North Dakota to Illinois.
While today's decision does not kill the project outright, the analysis is expected to take months, and the company has indicated that contracts will fall through if the pipeline does not go into service on schedule.
The company did not immediately respond to a request for comment, but supporters of the pipeline denounced the decision as "purely political" and urged President-elect Donald Trump to take action after he takes office.
"With President-elect Trump set to take office in 47 days, we are hopeful that this is not the final word on the Dakota Access Pipeline," Craig Stevens, spokesman for the Midwest Alliance for Infrastructure Now, said in a statement.