“They are not going to get away with this," Navajo Nation President Russell Begaye told residents of the New Mexico portion of the reservation. Photo by Rick Abasta / Office of the Navajo Nation President

The Navajo Nation will sue the Obama administration over the release of mine waste into the water supply, President Russell Begaye said over the weekend.

About three million gallons of orange-colored waste was accidentally spilled at the Gold King Mine in Colorado last week, the Environmental Protection Agency admitted. The contaminants have already made their way downstream to the New Mexico portion of the Navajo Nation.

Although drinking water on the reservation remains unaffected, Begaye and other tribal officials have issued strong warnings to their citizens. They should not allow livestock to drink from the San Juan River, enter the river or otherwise use the water from the river due to concerns about dangerous levels of arsenic, metals and other toxins from the mine waste.

“They are not going to get away with this,” Begaye told concerned tribal members who packed into the Shiprock Chapter House on Saturday to hear about the disaster.

The scene of the spill at the Gold King Mine in Colorado. Photo from EPA

In addition to signing a disaster declaration for the reservation, Begaye authorized the Navajo Nation Department of Justice to take "immediate action" against the EPA. He indicated that the tribe will seek damages to address the costs of clean up, along with the costs of providing water, food and other supplies to the families affected.

“The San Juan River is their lifeline," Begaye said of residents in the area. "We want full disclosure on what chemicals were released into the river. We understand cleanup will take decades. We demand cleanup of this water and the sediments of our affected rivers immediately."

The spill, which occurred last Wednesday, continues to spread. The waste is expected to reach Lake Powell, a major tourism and recreation area further down the river in Utah and Arizona, by Wednesday.

"While contaminant levels and impacts anticipated at Lake Powell are not yet understood, as a precautionary measure, the National Park Service at Glen Canyon National Recreation Area is encouraging visitors to avoid drinking, swimming or recreating on the San Juan River within Glen Canyon National Recreation Area and on the San Juan River arm of Lake Powell until further notice," the Glen Canyon National Recreation Area said in a press release.

Tribal members met at the Shiprock Chapter House in New Mexico on August 8, 2015, to discuss the spill. Photo by Rick Abasta / Office of the Navajo Nation President

Officials in Colorado and New Mexico have joined the Navajo Nation in blasting the EPA for its handling of the disaster. Some residents of Colorado have seen chemicals in their drinking wells and two counties in that state have declared disasters.

"We will hold the EPA accountable," Sen. Michael Bennet (D-Colorado) said on Twitter after visiting the affected area on Sunday. "Right now our main concern is addressing this blowout and ensuring safe water."

The Gold King Mine is an abandoned mine in San Juan County The waste was being held being some debris before it was accidentally released into the Animas River, which feeds into the San Juan River. Both are a part of the larger Colorado River System, where Lake Powell lies further west.

"EPA is committed to working closely with response agencies and state and local officials to ensure the safety of citizens, respond to concerns and to evaluate impact to water contaminated by the spill. EPA teams are deployed throughout the Animas River corridor collecting data," the agency said on its emergency response page. "EPA Region 8 is also in close coordination with Region 6 and Region 9 and the states of Colorado, New Mexico, Utah, Southern Ute Tribe and Navajo Nation."

Navajo President Begaye visited the site on Sunday and posted a Navajo-language video and an English one to explain how the spill occurred and how the EPA is responding to it. One of them shows how the mine waste continues to trickle from the debris pile.

"The water is still running. They don't want to block it off because they don't know what's back there," Begaye said as he pointed toward the pile.