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Water Quality Permit of Interest

Pinyon Plain Mine

Revised On: Jul. 8th, 2026 - 02:21 pm

This site/facility of interest online resource provides interested parties easy access to permits and documents for Pinyon Plain Mine, owned by Energy Fuels Resources (USA) Inc. (EFRI), formerly Canyon Mine.

Water Quality Permitting*

On July 6, 2026, ADEQ issued an “other” amendment to the Individual APP Permit No. 113481 to EFRI for Pinyon Plain Mine. The purpose and scope of the APP is to ensure that facilities are designed, constructed, and operated in a manner that eliminates or minimizes the impact of the facility’s operation on groundwater quality through operation, closure, and post-closure.

Other Amendment (2026)

EFRI submitted its amendment application on Nov. 19, 2025, which was revised on Jan. 14, 2026. The application, initially classified as a “Minor” amendment, was changed to an “Other” amendment on June 23, 2026, in response to Consultation with the Havasupai Tribe. ADEQ published the public notice for the amendment on ADEQ’s Permits in Process webpage in November 2025, followed by a second public notice posted to ADEQ’s public notice webpage on June 25, 2026, and printed in the Arizona Daily Sun on June 27, 2026. Pursuant to Arizona Administrative Code (A.A.C.) R18-9-A211(E), Other Amendments do not include a public comment period.

The facility also has an Arizona Pollutant Discharge Elimination System (AZPDES) Industrial Stormwater Mining Multi-Sector General Permit | Learn More About MSGP >

Documents

Environmental Impact Statement (EIS) — The 1986 decision to issue the EIS was upheld in appeals and court cases. Additional facility history, court decision documents, and related information are available on the United States Forest Service Pinyon Plain Mine webpage | Visit Website >

  • U.S. Geological Survey (USGS): Investigation of Hydrogeologic Conditions in the Subsurface near Pinyon Plain Uranium Mine in the Grand Canyon Region | View > 
Compliance Reports

Quarterly water quality monitoring results as required by the Individual APP permit:

  • The facility monitors the quality of the discharge from the outflow pipe from the mine shaft and into the lined impoundment with as well as four Point of Compliance (POC) groundwater monitoring wells: 
  • POC #1, POC #2, and POC #3 wells are in the Coconino aquifer
  • POC #4 well is in Redwall-Muav aquifer
  • These POC wells are sampled to measure groundwater quality in comparison to established limits, which were based on natural groundwater conditions for the site.

The permit has set Alert Levels (ALs), which serve as early indicators, set below the Aquifer Quality Limit (AQL). The AQL is established as the level the facility must not exceed to be protective of groundwater quality.

The quarterly results show the date of sample collection, sampling frequency, the sampling results for each parameter with the associated monitoring point(s). Where applicable, the established limits for each parameter are included for groundwater monitoring in the form of ALs, and AQLs.

*For older permits and documents, please submit a records request | Submit > 

For more information about Pinyon Plain Mine, visit the Site/Facility of Interest section within the My Community page | View Page >

Looking for air quality permitting related to this facility? | View >