oEPA
NAVAJO NATION
ABANDONED URANIUM MINES
U.S. Environmental Protection Agency • Region 9 • San Francisco, CA • March 2018
Cove Area Abandoned Uranium
Mines Investigation Activities
Cove Wash Watershed Assessment
From 2015 to 2017, the U.S. Environmental Protection Agency (USEPA), along with Navajo Nation EPA and Dine
Environmental Institute of Dine College, sampled sediment and water in the Cove Wash watershed and conducted
various surveys and studies. Sampling determined that the watershed has elevated uranium concentrations in surface
and ground water around and below the historically mined areas. Sampling goals included:
1.	Identifying sources of contamination and potential areas of concern.
2.	Determining the baseline contaminant levels in the Cove Wash.
The types of sampling completed are shown in the table below During the time sampling occurred, USEPA also
installed warning signs at unregulated water wells. Upcoming activities include livestock assessments and air sampling.
About the Cove Wash
Watershed
The Cove Wash watershed is approximately 47
square miles and includes 42 abandoned uranium
mines within the Lukachukai Mountains. Year-
round water is found in peaks and canyons above
7,000 feet elevation, where springs and seeps are
above ground. Developed springs and wells are also
part of the watershed.
| HUMANS SHOULD
NOT DRINK FROM
THIS WATER SOURCE
Water well warning signs installed at unregulated
water wells.
Completed
Cove Wash spring snowmelt sampling
Cove Wash low-flow sampling
Mexican spotted owl survey
Cove Wash wetland survey
Crop and irrigation study
Sampling in the Cove Wash watershed

-------
Remedial Investigation/Feasibility Study Activities for the
Cove-Area Tronox Mines
In late June 2016, USEPA entered into an agreement with the U.S. Army Corps of Engineers (USACE) to develop a
planning document for addressing the Cove Chapter abandoned uranium mines. This planning document is called a
conceptual site model (CSM). The CSM will help USEPA figure out which areas need further study and which areas
will move straight to cleanup. USACE presented an introduction to the CSM to the Cove community in November
2016 and received their feedback.
As part of the agreement, USACE will also do an assessment that identifies mining areas where more data will need
to be collected. To complete the assessment, USACE created picture models that show how exposure to uranium can
occur and to whom.
Next Steps for the CSM
Results of the CSM will be presented to the Cove community in Spring 2018.
Superfund Process on the Navajo Nation
Assessment
Decision Making
Clean Up
I
uli
0"
~=
i' &=
r! i=
Access
Agreements
Resources
Surveys
Signs and
Fences
Removal Site
Evaluation
Engineering
Evaluation /
Cost Analysis
Łą3
Public
Comment
Period
Action
Memorandum
o*ov
Removal
Action

Community Involvement and planning for a site's future are ongoing throughout the process
Coordination with the Navajo Nation government including NNEPA, Navajo AML, and the Dine Uranium Remediation Advisory Commission
For More Information
If you have questions about the Cove Wash Watershed Assessment and Remedial Investigation/Feasibility
Study, please contact:
Gaelle Glickfield
Remedial Project Manager
USEPA Region 9
(415) 972-3045
glickfi eld.gaelle@epa .gov
Secody Hubbard
Community Involvement Coordinator
USEPA Region 9
(415) 972-3241
hubbard.secody@epa.gov
For more information visit:
www.epa.gov/navaio-nation-uranium-
cleanup/cove-arizona-mines-cleanup
o
Printed on 50% post-consumer recycled paper
Processed chlorine-free

-------