Science for Decision Making on Uranium Mining in Arizona

Pinenut Mine

The Pinenut Mine is in the Arizona Strip (the area of Arizona north of the Colorado River), approximately 35 miles south of Fredonia and 4 miles west of Kanab Creek, in Mohave County. It was first mined in the 1980s, went on standby from 19891 until 2013, and then was mined again from 2013 until 2015 when it closed permanently2.

Milling was not done on site; all ore was shipped to a mill near Blanding, Utah1. Shipment of stockpiled ore continued after the mine closed2. It produced approximately 530,000 pounds of uranium oxide in the 1980s3 and an additional 881,000 pounds of uranium oxide from 2013-2016 for a total of about 1.4 million pounds of uranium oxide. Reclamation began in 2018 and as of early 2020 the 18-acre site was completely reclaimed except for the water well and associated facilities, and reseeding.

Soil and biological samples were collected in 2014-2015 to characterize chemical and radiochemical concentrations and distribution of radiation around the mine during active mining. Radon concentrations in air were monitored during active mining and storage of ore at the surface in 2015 and 2016. Soil samples were collected in 2018 to characterize infiltration and chemical characteristics of the shallow subsurface (the unsaturated zone) after mining. A water supply well for the Pinenut and Arizona 1 mines has been periodically sampled since 2009. Additional sampling may occur once reclamation is complete.

Mine Location

Mine Site Maps 20200921 Pinenut sm

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Pinenut lg little

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Base map images are the intellectual property of Esri and are used herein under license. Copyright © 2016 Esri and its licensors. All rights reserved.

Activities

Activities listed below are scientific research studies occurring at this site. Studies within the Grand Canyon region are grouped by theme and each theme has specific tasks (referenced by task number).

The View Activity button below each task will open a separate window with detailed activity information.

Biology

Analyze Ecological Risk of Contaminant Concentrations at Breccia Pipe Uranium Mines

  • GCSP Tasks: 15
  • Status: Completed

 

Characterizing Vegetation Communities at Breccia Pipe Deposits through the Mine Life Cycle

  • GCSP Tasks: 7a
  • Status: Ongoing

 

Environmental DNA at Mine and at Reference Locations

  • GCSP Tasks: 7a
  • Status: Completed

 

Exposure Characterization in Plants and Animals through the Mine Life Cycle

 

Migratory Bird Surveys

  • GCSP Tasks: 5a
  • Status: Ongoing

 

Mine Utilization by Bats and Amphibians

  • GCSP Tasks: 5a , 7a
  • Status: Ongoing

Soil

Characterize Aeolian Transport across the Mine Life Cycle

  • GCSP Tasks: 11
  • Status: Ongoing

 

Characterize Element Mobility and Bioavailability in Soil Samples

 

Characterize Surface Radiation and Soil and Dust Chemistry through the Mine Life Cycle

 

Characterizing Changes in Surface Radiation Using Autonomous Radon Meters and a Time-Lapse Camera at the Pinenut Mine

 

Quantify Water and Uranium Movement in the Unsaturated Zone at Sites through the Mine Life Cycle

Water

Investigating Potential Impacts from Uranium Mining on Grand Canyon Regional Groundwater Resources

Aerial Images

1992

Pinenut 1992 small

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Base map data from Google, U.S. Geological Survey, 1992.

2015

Pinenut 2015 small

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Base map data from Google, 2015.

2019

Pinenut 2019 small

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Base map data from Google, 2019.


Sources:

1 Alpine, Andrea E., ed., 2010, Hydrological, geological, and biological site characterization of breccia pipe uranium deposits in northern Arizona: U.S. Geological Survey Scientific Investigations Report 2010—5025, 353 p., 1 pl., scale 1:375,000

2 Energy Fuels Inc., 2015, Energy Fuels Announces Results for the Three Months Ended September 30, 2015: Oil and Gas 360 Newsletter

3 Ross, D.A., and Moreton, Christopher, 2012, Technical report on the EZ1 and EZ2 breccia pipes, Arizona Strip district, U.S.A.: NI 43-101 Report prepared by Roscoe Postle Associates Inc. for Energy Fuels Inc., 92 p.