The Environmental Protection Agency has decided not to pay damage claims totaling $1.2 billion from the Gold King Mine disaster in August 2015.

EPA officials on Friday said the agency conducted a legal analysis and concluded that sovereign immunity protects the EPA team that was working on the mine when it accidentally triggered a 3 million gallon deluge of acidic, heavy metals-laden drainage into headwaters of the Animas River above Durango in southwestern Colorado.

“What we determined was that we had no legal authority to pay,” an EPA official told The Denver Post, speaking on condition of anonymity because agency policy doesn’t allow officials to speak to the media for attribution.

“Only Congress can authorize people to sue the government, and what the EPA did was not something Congress has said we can be sued for,” the official said in a phone interview. “You want government officials to be able to go in and not hold back on using their judgment because they are worried they will be sued.”

At least 73 claims were filed against the EPA seeking a total $1.2 billion compensation for alleged damages to crops that could not be watered, livestock that required to clean water, contaminated wells, lost tourism business, lost wages for tourism sector workers and local government expenses.

The 31 claims from people in Colorado sought a total of $1.5 million. New Mexico residents filed 33 claims seeking $1 billion.

Colorado Gov. John Hickenlooper sent out a statement that read in part: “We expected the EPA to make good on its promise to reimburse any Colorado resident or business that suffered a legitimate loss as a result of the spill. The Attorney General has agreed to help us find ways we can make sure our residents receive just compensation.”

The claims from the Navajo Nation sought $160 million. Those claims included $159 million to find alternative water and monitoring water in the future. The contaminated water spilled into the Animas River, which feeds into the San Juan River in New Mexico. The San Juan flows through the Navajo Nation and into Utah, where it meets the Colorado River.

Utah residents sought $122,000, and a trip planner in Massachusetts sought $1,200 for a canceled trip. EPA attorneys late Thursday mailed 73 letters to claimants conveying that their claims have been reviewed but that no relief was available.

Under the Federal Tort Claims Act, the claimants now have six months to file legal challenges to that decision.

New Mexico Attorney General Hector Balderas vowed to keep fighting for compensation.

“Our families and farmers rely on this water, and I will continue to aggressively pursue litigation to obtain justice for our culturally unique population and fragile economy,” he said in a news release.

Colorado Sens. Michael Bennet, a Democrat, and Cory Gardner, a Republican, and Republican Rep. Scott Tipton sent out a joint statement voicing their displeasure with the agency’s decision.

“After the EPA’s irresponsible actions led to the release of 3 million gallons of contaminated water into Cement Creek and the Animas River, the agency said it would make sure that wronged parties were made whole,” said Tipton, who represents the district in southwestern Colorado. “The news today is a complete departure from that commitment, and our states, local governments, and tribes can rest assured that we will continue to work to make the EPA accountable for the mess they have made.”

In December, the EPA paid out $4.5 million to local, state and tribal governments to cover the emergency response costs from the days after the Aug. 5, 2015, spill but rejected requests for another $20.4 million for other expenses.

In October 2016, the U.S. Attorney in Denver said his office would not prosecute an EPA employee involved in the Gold King Mine disaster, leaving it to the agency to determine administrative action against the employee. The decision was based on information submitted by the EPA’s Office of Inspector General to federal prosecutors after a year-long internal probe.

Sens. John McCain of Arizona and John Barrasso of Wyoming, members of the Senate Committee on Indian Affairs, in May sent a letter to Attorney General Loretta Lynch urging a criminal probe.