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News Releases from Region 09

EnPro Holdings, Inc. Agrees to Assess Eight Mines Near Cameron, Ariz.

Work Expected to Cost $500,000

Contact Information: 
Margot Perez-Sullivan (

For Immediate Release: January 8, 2018

SAN FRANCISCO - For over ten years, EPA has worked in close coordination with the Navajo Nation to address contamination at over 500 abandoned uranium mines on and near the Navajo Nation. Today, the Environmental Protection Agency (EPA) announced a settlement under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA or the Superfund Law) worth $500,000 with EnPro Holdings, Inc. to assess eight abandoned uranium mines located on the Navajo Nation, near Cameron and Tuba City, Arizona.

The eight abandoned uranium mines were originally operated by the A&B Mining Corporation in the 1950s.  A+B Mining Corporation's operations contributed to the contamination at these eight sites and made them liable for the cleanup under CERCLA. Through a series of mergers between 1959 and 2016, EnPro Industries became the corporate successor to A&B Mining Corporation. In 2012, the EPA, in partnership with the Navajo Nation, developed a list of 46 “high priority” abandoned uranium mines based on radiation levels, proximity to homes and potential for water contamination.  Two of the mines EnPro has agreed to assess are on the agency’s high priority list.  EPA projects that EnPro will complete the assessment of the eight sites under this settlement by the end of 2019.

Under the agreement, EnPro will coordinate with EPA and the Navajo Nation in performing radiation assessments, installing fencing and signs warning residents and visitors of potential exposure, and preparing cultural resources and biological surveys. The agreement also requires EnPro to pay EPA’s oversight costs.

During the Cold War, 30 million tons of uranium ore were mined on or adjacent to the Navajo Nation, leaving more than 500 abandoned mines. Since 2008, EPA has conducted preliminary investigations at all the mines, remediated 51 contaminated structures, provided safe drinking water to 3,013 families in partnership with the Indian Health Service, and performed cleanup or stabilization work at nine mines. In total, EPA has reached enforcement agreements and settlements valued at $1.7 billion to reduce the highest risks of radiation exposure to the Navajo people from abandoned uranium mines. As a result, funding is now available to begin the assessment and cleanup process at 219 of the 523 abandoned uranium mines. Cleanup of the of abandoned uranium mines is a closely coordinated effort of EPA and the Navajo Nation.

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Superfund Task Force. In May 2017 Administrator Scott Pruitt established a task force to restore EPA's Superfund program to its rightful place at the center of the Agency's core mission to protect health and the environment. Click here to learn more.