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Reference News Release: EPA orders mine cleanup work at Smith Lake and Mariano Lake Areas

Release Date: 08/28/2014
Contact Information: Margot Perez-Sullivan, (415) 947-4149,

SAN FRANCISCO – The U.S. Environmental Protection Agency has reached an agreement with Homestake Mining Company of California requiring the company to assess contamination and address safety hazards at four abandoned uranium mines in the Mariano Lake and Smith Lake areas on the Navajo Nation. The EPA and the Navajo Nation will oversee the work.

“EPA has a polluter pays policy that seeks to make those responsible for environmental damage pay for the cleanup,” said Jared Blumenfeld, EPA’s Administrator in the Pacific Southwest Region. “This work, which will cost about $500,000, is another element in our partnership to deal with the toxic legacy of abandoned uranium mines.”

Under the agreement, Homestake will set aside funds for EPA’s oversight of future cleanup.

Over the next several months, Homestake will conduct extensive radiation surveys of the mine sites to assess risks, backfill open holes and mitigate surface features that pose physical threats to people or animals. The company will also post bilingual (English/Navajo) warning signs around the mine sites and sample surface and subsurface soils in the areas around the mines. This work is the first phase of cleaning up the uranium contamination at the four mine sites, and is expected to be completed by fall 2015.

This work at the Mariano Lake and Smith Lake sites is part of a broader program to screen, assess, and clean up abandoned uranium mine sites throughout Navajo Nation. In 2008, the EPA in partnership with the Department of Energy, Bureau of Indian Affairs, Indian Health Service and Nuclear Regulatory Committee developed a five year plan to address the legacy of abandoned uranium mines on the Navajo Nation. For more information on past accomplishments, please visit: