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  1. Home
  2. Navajo Nation: Cleaning Up Abandoned Uranium Mines
  3. Abandoned Mines Cleanup
  4. WESTERN REGION

EnPro Holdings Inc. (EnPro) Mines

EnPro Holdings Inc. (EnPro) mines are eight abandoned uranium mine claims located along the Little Colorado River or Highway 89 near Cameron, AZ. Under a 2017 Administrative Order on Consent, EnPro agreed to perform assessments for radium-226, uranium, arsenic, molybdenum, selenium and vanadium at these mine sites.

Background | Current Work | Community Involvement | Cleanup Timeline | Photos

Site Facts

EnPro Holdings Inc. is responsible for assessing eight of the 111 abandoned uranium mine claims in the region. Two of these eight mines are “priority mines”.

Documents

  • Map of the Western Abandoned Mine Region
  • Fact Sheets
  • Community Involvement Plan
  • EnPro Holdings, Inc. Administrative Settlement Agreement and Order on Consent (pdf) (6.92 MB, 11/8/2017)
  • A&B No.2 Site Screen Report
  • A&B No.3 Site Screen Report

Site Contacts

Remedial Project Manager
Estrella Armijo
(armijo.estrella@epa.gov)
(415) 972-3859

Community Involvement Coordinator
Priscilla Tom
(tom.priscilla@epa.gov)
(505) 240-0093

Background

Mines in the Cameron area of Navajo Nation were operated in the 1950s and 1960s by a number of different companies before being abandoned. While the Navajo Nation Abandoned Mines Lands program addressed many of the physical hazards associated with these mines, EPA and Navajo Nation EPA (NNEPA) are working to address remaining chemical and radiological hazards that may pose a risk to community members.

In 2017 EPA signed a legal agreement called an Administrative Order on Consent (pdf) with EnPro to assess eight mine claims in western Navajo Nation. More information about work taking place in the region can be found in the Western Abandoned Uranium Mine (AUM) Region.

Current Field Work and Investigations

EnPro began field work in the Cameron area in 2017 under EPA and NNEPA. Field work includes:

  • EPA is drafting an Engineering Evaluation/Cost Analysis for the. AB No. 2 and AB No. 3 sites
  • EPA is in the decision-making phase for AB No.3 and AB No.2 and in the assessment phase for the Bodaway Gap Sites (6 mines).

Community Involvement

In the communities of Cameron and Coalmine Canyon, residents should know and participate in what EPA is doing in their community and have a say in it. The main purpose of engaging community members is to give them the opportunity to become involved in EPA’s activities and help shape the decisions that are made affecting their community.

To further this goal, EPA developed the Western Navajo Abandoned Uranium Mine Region Community Involvement Plan with input from community members. The Community Involvement Plan is a living document to guide community members and EPA in meaningful information sharing regarding cleanup activities in the Western Abandoned Uranium Mine Region.

Cleanup Progress Timeline

2022

Removal Site Evaluation Report: EnPro Holdings Inc. (pdf) (243.66 MB, September 29, 2022)
Removal Site Evaluation Report for EnPro Holdings Inc. Abandoned Uranium Mines A&B No. 2 and A&B No. 3, Cameron Chapter, Navajo Nation, Coconino County, Arizona. [NOTE: VERY LARGE FILE! RIGHT-CLICK (OR ALT-CLICK) AND SAVE TO YOUR DESKTOP]

2017-2020

  • Obtained access agreements from homesite lease and grazing permit holders 
  • Completed ecological and cultural resource surveys 
  • Placed warning signs at all mine sites 
  • Completed preliminary gamma radiation surveys of the eight EnPro mine claims 
  • Submitted Draft Final Remedial Site Investigation Reports for Priority Mines A&B No. 2 and A&B No.3

Site Photographs

EnPro Holdings Inc.
  • Desert Landscape showing EnPro Holdings Inc. A&B No. 2 Abandoned Mine Site

    A&B No. 2 Abandoned Mine Site

  • A&B No. 3 Abandoned Mine Site adjacent to the Little Colorado River

    A&B No. 3 Abandoned Mine Site adjacent to the Little Colorado River

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 April 3, 2025
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