As Nebraska's Keystone XL pipeline hearings came to a close on Thursday, Indigenous tribes and environmentalists vowed to put their "bodies on the line" to stop a project they have argued would be a "disaster for people, wildlife, and the planet."

"As the state of Nebraska stands poised to make a potentially life-altering decision about permitting this poisonous bitumen to be inflicted on its population, we stand poised to protect all life now and in the future."

—Larry Wright Jr., Ponca Tribe of NebraskaThe hearings lasted a total of four days. On the final day of the meetings—which featured both supporters and opponents of the $8 billion, 1,100 mile pipeline—over 461,000 public comments were delivered to the Nebraska Public Service Commissioners protesting the project, 350.org noted in a statement.

"The amount of opposition to the Keystone XL pipeline is clear," said Bold Nebraska founder Jane Kleeb. "Our water, property rights, climate and the Sovereign Rights of Native Nations are in the public interest and must be protected from this foreign tar sands pipeline."

Keystone hearings just wrapped in Nebraska. Decision expected in Oct/Nov. Wonder what side of history neb_psc will choose to be on? #NoKXL pic.twitter.com/hW8dObbwh7 — Mike Hudema (@MikeHudema) August 10, 2017

Earlier this week, over 150 Indigenous tribes from the U.S. and Canada signed the Treaty Alliance Against Tar Sands Expansion, which expresses opposition to several pipeline projects, including TransCanada's Keystone, Enbridge's Line 3, and Kinder Morgan's Trans Mountain Expansion.

In a report published last week, Greenpeace labeled these pipelines "The Dirty Three," and disputed industry claims that they do not pose a threat to the environment.

"Despite industry claims, pipeline spills have remained a steady problem," the report concluded. "Extrapolating from current rates of incidents, Keystone XL can expect 59 significant spills in a 50-year lifetime."

"As the state of Nebraska stands poised to make a potentially life-altering decision about permitting this poisonous bitumen to be inflicted on its population," Larry Wright Jr., chairman of the Ponca Tribe of Nebraska, said of Keystone, "we stand poised to protect all life now and in the future."

"The Nebraska Public Service Commission faces a clear choice: Stand with a foreign oil company that has publically admitted they might not build this pipeline even if they get the permits, or stand with the people of Nebraska and a renewable energy future."

—Collin Rees, Oil Change InternationalThe Nebraska Public Service Commission is scheduled to make a final decision on whether to approve the pipeline on November 23. If the project is allowed to move forward, the resulting civil disobedience will make Standing Rock look like a "dress rehearsal," Kleeb said.

Keystone has faced fierce opposition since it was commissioned in 2010, and that opposition has only intensified since President Donald Trump effectively revived the project earlier this year.

"The project has pitted landowners and environmentalists worried about greenhouse gas emissions, oil spills, and environmental contamination, against business advocates who say it will lower fuel prices, shore up national security, and bring jobs," Reuters summarized.

Collin Rees, a campaigner for Oil Change International, put the conflict in more stark terms.

"The Nebraska Public Service Commission faces a clear choice: Stand with a foreign oil company that has publically admitted they might not build this pipeline even if they get the permits, or stand with the people of Nebraska and a renewable energy future," Rees said in a statement on Thursday. "Native tribes, farmers, ranchers, Nebraskans, and millions of activists around the globe have been fighting this Keystone XL for years, and they'll keep fighting until it's stopped for good."