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Case Summary: $600 Million Settlement to Clean up 94 Abandoned Uranium Mines on the Navajo Nation

On May 22, 2017, the U.S. District Court for the District of Arizona entered the settlement agreement between the U.S. Environmental Protection Agency (EPA), the Navajo Nation, and two affiliated subsidiaries of Freeport-McMoRan, Inc. for the cleanup of 94 Abandoned Uranium Mines on the Navajo Nation. The settlement is valued at over $600 million.

Cyprus Amax and Western Nuclear, the affiliated subsidiaries of Freeport-McMoRan, will perform removal site evaluations, engineering evaluations and cost analyses, and cleanups at the 94 mines. The United States on behalf of the Department of the Interior and the Department of Energy, will place $335 million into a trust account to help fund the cleanup. With this settlement, funds are now committed to begin the cleanup process at over 200 abandoned uranium mines (AUM) on the Navajo Nation.

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Information about Freeport-McMoRan and Affiliated Subsidiaries

Freeport-McMoRan, Inc. is a mining company based in Pheonix, Arizona. The company is the world’s largest producer of molybdenum, and the second largest producer of copper. The affiliated subsidiaries of Freeport-McMoRan performing the cleanup work are:

  • Cyprus Amax (a successor-in-interest to Vanadium Corporation of America and Climax Uranium Company established in 1993 through the merger of Cyprus Minerals Company and Amax Inc. and
  • Western Nuclear

Information about Abandoned Uranium Mines on the Navajo Nation

From 1944 to 1986, nearly 30million tons of uranium ore were extracted from Navajo lands under leases with the Navajo Nation. EPA has identified 523 abandoned uranium mines on the Navajo Nation (NN), encompassing more than 27,000 square miles within Utah, New Mexico and Arizona.

The unique geology of the region makes the Navajo Nation rich in uranium, a radioactive ore in high demand after the development of atomic power and weapons at the close of World War II.

The federal government, through the Atomic Energy Commission (AEC), was the sole purchaser of uranium until 1966, when commercial sales of uranium began. The AEC continued to purchase ore until 1970. The last uranium mine on the Navajo Nation shut down in 1986.

Many Navajo people worked in and near the mines, often living and raising families in close proximity to the mines and mills where ore was processed. Since 2008, federal agencies—including EPA, the Department of Energy, the Bureau of Indian Affairs, the Department of the Interior, the Nuclear Regulatory Commission and the Indian Health Service—have collaborated to address uranium contamination on the Navajo Nation.

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Contact Information

For more information, contact:   

Laurie Williams
Assistant Regional Counsel
U.S. Environmental Protection Agency
Region 9
75 Hawthorne St.
San Francisco, California  94105

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