Pacific Southwest, Region 9
Serving: Arizona, California, Hawaii, Nevada, Pacific Islands, Tribal Nations
Addressing Uranium Contamination
on the Navajo Nation
2014 Navajo Nation Five-Year Plan (PDF)
(40 pp, 1.4M)
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The lands of the Navajo Nation include 27,000 square miles spread over three states in the Four Corners area. The unique geology of these lands makes them rich in uranium, a radioactive ore in high demand after the development of atomic power and weapons at the close of World War II in the 1940s.
From 1944 to 1986, nearly four million tons of uranium ore were extracted from Navajo lands under leases with the Navajo Nation. Many Navajo people worked the mines, often living and raising families in close proximity to the mines and mills.
Today the mines are closed, but a legacy of uranium contamination remains, including over 500 abandoned uranium mines (AUMs) as well as homes and drinking water sources with elevated levels of radiation. Potential health effects include lung cancer from inhalation of radioactive particles, as well as bone cancer and impaired kidney function from exposure to radionuclides in drinking water.
US EPA maintains a strong partnership with the Navajo Nation and, since 1994, the Superfund Program has provided technical assistance and funding to assess potentially contaminated sites and develop a response. In August 2007, the Superfund Program compiled a Comprehensive Database and Atlas assessments of all known uranium mines on the Navajo Nation.
In October 2007, at the request of the U.S. House Committee on Oversight and Government Reform, EPA, along with the Bureau of Indian Affairs (BIA), the Nuclear Regulatory Commission (NRC), the Department of Energy (DOE), and the Indian Health Service (IHS) developed a coordinated Five-Year Plan (PDF) (2 pp, 1.0M) to address uranium contamination in consultation with Navajo Nation EPA.
In January 2013, six federal agencies, in consultation with the Navajo Nation, completed a five-year effort to address uranium contamination in the Navajo Nation. The effort focused on the most imminent risks to people living on the Navajo Nation. While the last five years represent a significant start in addressing the legacy of uranium mining, much work remains and the same federal agencies have collaborated to issue a second Five-Year Plan (PDF) (40 pp, 1.4M). The purpose of the second Five-Year Plan is to build on the work of the first plan, make adjustments based on information gained during this period, and plan the next steps in addressing the most significant risks to human health and the environment.
Although the legacy of uranium mining is widespread and will take many years to address completely, the collaborative effort of US EPA, other federal agencies and the Navajo Nation will bring an unprecedented level of support and protection for the people at risk from these sites. Much work remains to be done, and US EPA is committed to working with the Navajo Nation to remove the most immediate contamination risks and to find permanent solutions to the remaining contamination on Navajo lands.
US EPA, SFD 6-3
75 Hawthorne St
San Francisco, CA 94105
Toll Free 1 (800) 231-3075
Fax (415) 947-3528
Navajo Nation EPA
P.O. Box 339
Window Rock, Arizona 86515