Newmont Corp. subsidiaries Newmont USA Ltd. and Dawn Mining Co. LLC agreed to clean up the abandoned Ross Adams uranium mine in southeast Alaska, which is in a semiremote region of the Tongass National Forest, the U.S. Forest Service said July 8 in a notice published in the Federal Register.

The two companies agreed to restore the site, at an estimated cost of US$7.2 million, to reduce to the risk of exposure to direct radiation and a range of safety hazards in order to resolve outstanding claims by the Forest Service that the companies violated federal Superfund law. The agency has been investigating the site in cooperation with Newmont and Dawn for over a decade. For several years, all entities have been negotiating the terms of a "mutually acceptable cleanup process," the notice said.

The agreement said the Forest Service's recommended method of cleanup includes excavating and transporting mine rock and mine-affected material to an open pit repository, which will be sealed to reduce radiation and inhalation of radon decay products. The companies will also be responsible for preventing access to the site to reduce recreational and occupational risk of exposure to radiation.

The mine began producing in 1957. Newmont entered into a joint venture in 1968 to explore the site and subleased the property to Dawn. In 1971, operations were shuttered due to weak uranium prices, and there has been no mining there since then.