Nicole Gaudiano

USA TODAY

WASHINGTON — Sen. Bernie Sanders called on President Obama to take action against the controversial Dakota Access oil pipeline during a protest outside the White House on Tuesday with members of the Standing Rock Sioux Tribe and other tribal nations.

The Vermont independent is seeking a full environmental and cultural impact analysis of the four-state, $3.8 billion project, designed to carry crude oil from North Dakota to Illinois. Federal officials last week temporarily halted part of the project, but Sanders wants the administration to go further, saying the pipeline threatens the environment and water resources and exploits Native Americans.

Protesters say the pipeline’s route under the Missouri River will endanger the water supply and sacred sites of the Sioux reservation located on the North Dakota-South Dakota border. A thorough analysis, Sanders said, will ultimately kill the pipeline.

"We cannot allow our drinking water to be poisoned so that a handful of fossil fuel companies can make even more in profits," the former Democratic presidential candidate told the cheering crowd, estimated at 3,000 by organizers. “We stand united in saying, ‘Stop the pipeline, respect Native American rights and let us move forward to transform our energy system away from fossil fuels.”

The protest was one of about 200 "#NoDAPL" events Tuesday, mostly in the United States, according to the environmental group 350.org.

It followed Tuesday's release of an internal memo from Energy Transfer Partners, the company building the Dakota Access pipeline, saying concerns about the pipeline’s impact on the water supply are “unfounded.” Kelcy Warren, the company’s chairman and CEO, also wrote that multiple archaeological studies conducted with state historic preservation offices found no sacred items along the route.

“We are committed to protecting and respecting the welfare of all workers, the Native American community, local communities where we operate, and the long-term integrity of the land and waters in the region,” Warren wrote in the memo, which was released to several media outlets.

Federal agencies on Friday temporarily halted the project on federal land bordering or under a reservoir and asked the company for a “voluntary pause” on construction near that area. That announcement came after a federal judge rejected the tribe’s request for a temporary injunction barring construction of the pipeline near their reservation.

Warren wrote that the company will meet with officials in Washington “to understand their position and reiterate our commitment to bring the Dakota Access Pipeline into operation.”

Sanders interpreted Warren's memo -- which states "the right of way for the entire pipeline has been obtained" -- as a refusal to halt construction while a new review takes place.

"In absence of the pipeline company’s compliance, further administration action is needed," he told the crowd at Tuesday's protest

A company spokeswoman said in an email, "We will construct only on land where we have the proper permits and approvals." She did not say if the company would comply with federal officials' request for a "voluntary pause," or if it would pursue construction on federal land that federal officials now say they won't authorize during a review.

Federal government halts work on part of pipeline

Q&A: The 4-state, $3.8 billion Dakota Access oil pipeline

Local law enforcement officials have accused protesters camped out near the site of assaulting private security guards hired by the company, while tribal officials said protesters have been bitten by security dogs. Arrest warrants were issued last week for Green Party presidential candidate Jill Stein and her running mate, Ajamu Baraka, after they spray-painted bulldozers during a protest.

At Tuesday's protest, Jasilyn Charger, 20, of the Cheyenne River Sioux Tribe, grew tearful while telling the crowd "there will be no warning for my people" if the pipeline breaks and pollutes their water. She and other tribal youths recently ran 2,000 miles from the Standing Rock Reservation to Washington to protest the pipeline.

"This is our land," Charger said. "This is our future."

Vermont author and environmentalist Bill McKibben, a key Sanders supporter who co-founded 350.org, skewered Democratic presidential nominee Hillary Clinton in a Sept. 7 Los Angeles Times op-ed calling on her to take a stand on the pipeline. He suggested a connection between her reticence and support from the fossil fuel industry and banks.

“The people who’ve built Clinton’s campaign war chest and her personal fortune are the same people who paid for the dogs that bit young native Americans,” wrote McKibben, who was tapped by Sanders to serve on the Democratic Party’s platform drafting committee.

A Clinton spokesman did not respond to a request for comment.

Addressing Native American issues and climate change were among Sanders’ priorities during his bid for the Democratic presidential nomination. The spinoff organization he launched, Our Revolution, is rallying his supporters to fight the pipeline.

“We have got to change the federal government’s relationship to the Native American people,” he said Tuesday. “The Native American people in this country have been taken advantage of for too long, they have been lied to, they have been exploited. That has got to change.”

Sanders offered an amendment to the Water Resources Development Act moving through Congress that would require an environmental impact statement before a certain easement could be granted for the pipeline. It was unclear Tuesday evening if the amendment will be considered.

Chase Iron Eyes of the Standing Rock Sioux reservation said he wants the pipeline killed but would settle for a rerouting of it.

"As a country, we need to respect what we call 'our first medicine,' which is water," he said before Tuesday's rally. "But it's good business to protect our water resources because energy security, agricultural security and national security flow directly from water security."

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