The White Mesa Mill in southern Utah is the last functioning uranium facility in the U.S.

The Grand Canyon Trust has released a report on the mill and how it affects neighboring tribal communities.

The mill is operated by Energy Fuels Incorporated.

The report says the company has quietly transformed its business model and now operates as a waste-disposal service; more than 700 million pounds of radioactive waste has been buried at the site.

The EPA recently barred the mill from accepting waste from Superfund sites, due to safety concerns. Members of the Trust and the Ute Mountain Ute tribe released the report at a press conference Tuesday.

“And we really need to look at closing this mill down," said Manuel Heart, chairman of the Ute Mountain Ute Tribe. "That's the bottom line from the Ute Mountain Ute Tribe, is the impact that it’s having from the water aquifer that meets the needs of all local and surrounding communities within southeast Utah, near the mill.” 

The report said that some of the waste has been transported from all over the nation and from overseas.