Indigenous communities and environmental organisations are concerned about a proposed licence change that would allow uranium company United Nuclear Corp (UNC) to transfer 765,000 cubic metres of waste from a mining area in western New Mexico to a nearby mill, Associated Press reported on 27 May.

As US nuclear regulators consider the licensing change, opponents say the proposal does not offer sufficient protection for and local Navajo communities that have already suffered from contamination of their land. Leona Morgan, Navajo community organiser told Democracy Now that there are 15,000 abandoned uranium mines across the country. And the Navajo Nation is working with the federal government to address at least 523 distinct mines on Navajo land.

Church Rock, New Mexico, is the site of the world’s largest uranium spill, when UNC’s tailings disposal pond breached its dam in 1979 resulting in the largest release of radioactive material in US history.

The spill released more than 1,000 tonnes of solid radioactive mill waste and 360,000 cubic metres of acidic, radioactive tailings solution into the Puerco River through Pipeline Arroyo. The spill contaminated groundwater and rendered the Puerco unusable to local residents, mostly Navajo peoples who were only warned belatedly of the toxic dangers from the spill.

In 2003, the Church Rock Chapter of the Navajo Nation began the Church Rock Uranium Monitoring Project to assess environmental impacts of abandoned uranium mines and found significant radiation from both natural and mining sources in the area. The Environmental Protection Agency (EPA) National Priorities List currently includes the Church Rock tailings storage site, where "groundwater migration is not under control”. A large number of epidemiological and environmental studies have shown continuing contamination of the land and impact on health.

Although the Navajo Nation appealed to the governor to request that the president declare the site a federal disaster area, he refused, reducing the aid available to local residents, and UNC continued operating the uranium mill until 1982.

The EPA and UNC removed 4,970 cubic metres of radium-contaminated soil surrounding five buildings, some residential, in 2007. The soil was moved to an off-site disposal facility. In 2008, the US Congress authorised a five-year plan for clean-up of contaminated uranium sites on the Navajo reservation. In 2005 the Navajo Nation passed the Diné Natural Resources Protection Act prohibiting uranium mining and processing in all its forms on Navajo land.

The Nuclear Regulatory Commission said it has coordinated with the tribe as it reviewed the potential environmental effects that would result from amending UNC's licence for the mill site. The mine waste that UNC wants to move to the mill site is made up of soil, vegetation, rock and other debris of varying levels of radioactivity. Officials say the higher-level waste would be disposed of elsewhere.

NRC’s review found that there would be only small environmental effects to surface and groundwater supplies, soil and air quality. However, it noted high impacts with respect to environmental justice given that residents in the area and the Navajo Nation more broadly have been suffering from the legacy of uranium mining and contamination for decades.

Activists have voiced concerns about the plan to consolidate the waste, saying it would not address the ongoing problems. They also are worried about the federal government removing a “potential threat waste” designation from the environmental impact statement.

The Red Water Pond Road Community Association, which is made up of residents who live near the site, has been pushing for the waste to be removed from the area altogether. Top Navajo government officials have made the same request, saying the waste remains a threat to human health and the environment.

In a recent letter to federal officials, Navajo President Jonathan Nez and Vice President Myron Lizer reiterated that those who are most affected by the waste are minority and low-income residents, and they are owed “the best solution possible." The Navajo leaders said that would be moving the waste to an appropriate repository away from the Navajo Nation. “Simply transporting it to a facility less than one mile away from the reservation boundary, while it technically is removing it from the Navajo Nation, in reality is just taking it from one side of the road to the other,” they wrote.

They went on to say that about 30 million tons of uranium were extracted from Navajo lands over decades to support the U.S. government's security mission. “It would seem appropriate for the United States to support the complete removal of the uranium waste that was improperly left behind from that effort,” they wrote. “If additional funding is needed to achieve that goal, such appropriations should be considered as well.”

Leona Morgan said the plan involves piling waste on top of the mill waste, at the site where the 1979 spill originated. “And the community is concerned because this is in a floodplain. And in the public meetings that were held in 2019, several community members expressed concern that this could result in a second Church Rock spill.”