Denver-based Energy Fuels Inc., one of the largest uranium producers in the United States, has signed a landmark agreement with the Navajo Nation on the transport of uranium ore along federal and state highways that cross through Navajo land. The agreement allows the resumption of uranium ore transport from Energy Fuels’ Pinyon Plain Mine in northern Arizona to the company’s White Mesa Mill in southern Utah, where the ore is processed into natural uranium concentrates (U₃O₈).

Energy Fuels has paused transport of uranium ore from its mine south of the Grand Canyon in Arizona to a processing facility in Utah—a path that crosses Navajo Nation land.

Members of the Navajo Nation are challenging the legality of uranium ore transport from a mine in Arizona across tribal lands to a processing facility in Utah.

A 2012 law bans uranium transport on the vast Navajo Nation land, which covers portions of Arizona, New Mexico, and Utah. Navajo Nation president Buu Nygren issued an executive order on Wednesday saying that there must be an agreement before uranium is transported through the reservation.