Cyprus Amax and Western Nuclear Mines

In 2017, the United States, on behalf of EPA and other federal agencies, entered into a historic settlement with Cyprus Amax Minerals Company (Cyprus Amax) and Western Nuclear, Inc. (Western Nuclear), subsidiaries of mining company Freeport-McMoRan, Inc., to clean up 94 mines on the Navajo Nation. This agreement addresses almost 20 percent of the abandoned uranium mines on the Navajo Nation.

Background

The mines are primarily located in the Four Corners area of the Navajo Nation and produced ore from the 1940s to 1985. One of these mines, Monument No. 2, near Monument Valley, Arizona, produced over 770,000 tons of ore and was the largest uranium mine in Arizona. The Ruby mines in Eastern Navajo produced a total of 790,000 tons of ore. The other mines covered by the settlement are relatively small and produced less ore.

Beginning in the 1990s, the Navajo Abandoned Mine Lands Reclamation Program eliminated the physical hazards at many of these mines by closing mine openings, burying mine waste, and reclaiming dangerous high walls. Cyprus Amax and Western Nuclear will clean up the mines after conducting detailed assessments and evaluating cleanup alternatives. EPA and the Navajo Nation Environmental Protection Agency (NNEPA) oversee all aspects of the work.

EPA and NNEPA prioritized 10 of these mines because they have elevated radiation and are near where people may live. In 2018, Cyprus Amax started conducting detailed assessments at these priority mines and an additional 22 mines to evaluate the extent of the area with potential mine waste contamination. Field work completed to date includes:

• Biological and cultural resource surveys
• Radiation surveys and soil samples

Legal Settlement

In 2017, the United States on behalf of EPA and other federal agencies entered into a historic settlement with Cyprus Amax and Western Nuclear to clean up 94 mines on the Navajo Nation. The settlement requires Cyprus Amax and Western Nuclear to perform the cleanup work, including paying EPA and NNEPA their costs in overseeing the cleanup work. The United States will pay for a portion of all costs through a $335 million trust fund. It is expected that the cleanup of the 94 mines will cost approximately $600 million.

This work will be performed over many years. Cyprus Amax and Western Nuclear worked with EPA and NNEPA to develop a schedule for performing work. That schedule includes completing detailed assessments at 30 mines in 2021, including priority mines. In 2021, Cyprus Amax will begin conducting detailed assessments at 32 mines in the Red Valley Chapter of the Navajo Nation.

The settlement includes cleanup of the Ruby Mines in Eastern AUM Region of the Navajo Nation. Separate legal agreements between EPA and Western Nuclear funded assessment of the Ruby Mines and evaluation of cleanup alternatives. Visit the Ruby Mines webpage for more information.

Community Involvement

Community members have an opportunity to become involved in the cleanup activities and help shape cleanup decisions. Cyprus Amax and Western Nuclear and their team of experts meet regularly—in coordination with EPA and NNEPA—with chapter officials, residents and community members to discuss the status of work at the mines.

These 94 mines are in the following abandoned uranium mines (AUM) regions and Navajo Nation Chapters. Click on the AUM regional pages below for community involvement updates and more information about the region.

• Northern AUM Region: Shiprock, Red Mesa, Red Valley, Sweetwater, Teec Nos Pos, and Cove Chapters
• Eastern AUM Region: Smith Lake Chapter
• North Central AUM Region: Kayenta, Oljato, and Dennehotso Chapters
• Central AUM Region: Chilchinbeto Chapter

Cleanup Progress Timeline

Cyprus Amax and Western Nuclear mines were operated from the 1940s to 1985. In 2017, the United States on behalf of EPA and other federal agencies entered into a historic settlement with Cyprus Amax and Western Nuclear Inc. for the cleanup of 94 mines on the Navajo Nation. Click on the different years below to learn about recent and upcoming activities.

1990s

• The Navajo Nation Abandoned Mine Lands Program performs reclamation activities to address physical hazards at most of the mine sites.

2017

• The United States on behalf of EPA and other federal agencies entered into a historic settlement with Cyprus Amax and Western Nuclear for the cleanup of 94 mines on the Navajo Nation.

2018-2023

• Cyprus Amax completed detailed investigations at 32 mines, including 10 priority mines. These mines are in the Cove Chapter, and the Tse Tah and Monument Valley areas.
• Cyprus Amax completed several Removal Site Evaluation reports that present the results of these field investigations.
• Cyprus Amax is conducing detailed investigations at a second group of 33 mines, one of which is a priority mine. These mines are in the Red Valley area.
• EPA, NNEPA, and Cyprus Amax continue to conduct community outreach in Cove, Red Valley, Red Mesa, Sweetwater, Tse Tah, Monument Valley, and Kayenta.

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