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  1. Home
  2. Navajo Nation: Cleaning Up Abandoned Uranium Mines
  3. Health Effects of Uranium

Water Sampling Results in the Navajo Nation

See also: Screening Assessment Report and Atlas with Geospatial Data

EPA is investigating if and to what extent abandoned uranium mines (AUMs) on the Navajo Nation have impacted groundwater and surface water.

EPA and the Navajo Nation agreed to assess potential impacts on water resources at four types of AUMs: surface mines, underground “dry” mines above groundwater, underground “wet” mines below groundwater, and “leach” mines where acid was used on site to extract ore.

To better understand potentially impacted water resources, in 2016 the United States and the Navajo Nation agreed to complete studies of two AUMs to determine if groundwater or surface waters have been affected by those mines.

Subsequently, in 2022 the U.S. and Navajo Nation agreed that these two water studies will be carried out under the newly created Phase 2 Expanded Trust Agreement (pdf) (753.67 KB, February 14, 2022) by the Phase 2 Expanded Trust (More information on the Phase 2 Expanded Trust can be found at Trust Mines). To this end, detailed surface water and groundwater studies are being conducted at Claim 28 mine in the Tachee-Blue Gap chapter and the Saytah/George Simpson 1 Incline mine in the Tolikan chapter by the Phase 2 Trustee, Derrith Watchman-Moore.

Separately, EPA is conducting a study to investigate potential impacts to surface water and groundwater from underground mines at the Northeast Church Rock/Quivira mining complex in the Church Rock chapter.

Finally, EPA will conduct a comprehensive investigation of potential impacts to surface water and groundwater in the Cove chapter as part of the Lukachukai Mountain Mining District remedial investigation and feasibility study.

Though these studies are ongoing, they are helping EPA to better understand the potential impacts to groundwater and surface water and to ensure that cleanup options implemented at abandoned uranium mine sites are protective of surface water and groundwater.

The following documents provide more information about EPA's work to provide safe drinking water to communities affected by uranium contamination.

Free viewers and readers are available to access documents on our website. If you encounter issues with assistive technology, please contact us.

  • Contaminated Unregulated Water Sources (pdf) (33.1 KB, November 13, 2012)
    This is a table with the results of testing of water sources in the Navajo Nation.
  • Northeast Church Rock Water Well Sampling 10/19/2010 (pdf) (3.72 MB, April 21, 2011)
    This is a report of water well sampling in the Northeast Church Rock area in 2011.
  • Navajo Nation Water Well Sampling 10/20-21/2010 (pdf) (2.48 MB, April 20, 2011)
    This is a report of water well sampling in various locations in the Navajo Nation in 2011.
  • Navajo Nation Unregulated Water Source Sampling 10/12-19/2009 (pdf) (74.49 KB, August 2010)
    This is a report of water well sampling of unregulated water sources in various locations in the Navajo Nation in 2009.
  • Navajo Nation Drinking Water Source Sampling 2/26 - 3/7/2008 (pdf) (8.67 MB, August 28, 2008)
    This is a report of water well sampling in various locations in the Navajo Nation in 2008.

Navajo Nation: Cleaning Up Abandoned Uranium Mines

  • Abandoned Mines Cleanup
    • CENTRAL REGION
      • Community Involvement Plans
      • CYPRUS AMAX & WESTERN NUCLEAR MINES
      • BLACK MESA MINING DISTRICT
    • EASTERN REGION
      • Community Involvement Plans
      • Fact Sheets
      • AMBROSIA LAKE MINES (TRONOX)
      • CYPRUS AMAX & WESTERN NUCLEAR MINES
      • MAC AND BLACK JACK MINES
      • MARIANO LAKE MINE (Old Gulf Mine)
      • NORTHEAST CHURCH ROCK MINE
      • OLD CHURCH ROCK MINE
      • QUIVIRA MINES
      • RUBY MINES
      • SECTION 32/33 MINES (TRONOX)
    • NORTH CENTRAL REGION
      • SKYLINE MINE
      • Community Involvement Plan
    • NORTHERN REGION
      • Community Involvement Plans
      • COVE AREA MINES
      • LUKACHUKAI MOUNTAINS MINING DISTRICT
      • CYPRUS AMAX & WESTERN NUCLEAR MINES
    • WESTERN REGION
      • Community Involvement Plans
      • Fact Sheets
      • Maps
      • EL PASO NATURAL GAS MINES
      • ENPRO MINES
      • SECTION 9 LEASE MINES
    • SUPERFUND NPL SITES (Lukachukai)
  • Administrative Records
  • ASPECT Aerial Survey
  • Atlas Screening Assessment Report
  • Community Involvement Plans
  • Contaminated Structures Program
  • Fact Sheets
  • Legal Documents and Settlements
    • TRONOX MINES
      • Fact Sheets
      • Financial Reports
      • Northern Agency RSE Report
    • TRUST MINES
      • Fact Sheet
      • Legal Document and Settlements
      • Technical Reports
  • Site Screen Reports
  • Ten-Year Plan (2020-2029)
    • Related Documents
  • Treatment Technology Pilot Studies
  • Health Effects of Uranium
    • Water Sampling Results
  • Contracting With EPA
    • Navajo Workforce Development
    • RAES Employment and Training Reports
Contact Us
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Last updated on May 5, 2025
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