On Sept. 29, 2026, a new comment period begins for the proposal to issue an air quality control permit to Minerals Research, Inc., for the operation of a copper slag processing facility located in Yavapai County, Arizona. The comment period ends Nov. 30, 2026.

Class II Air Quality Permit No. 100924

Permittee:

Minerals Research, Inc.

Facility:

Minerals Research, Inc.
705 E. Birch Street
Cottonwood, Arizona 86326
Yavapai County

The facility is subject to the requirements of federal and state clean air regulations. The facility emits the following air contaminants: coarse particulate matter with diameters 10 micrometers or less  (PM₁₀), fine particulate matter with diameters 2.5 micrometers or less (PM_2.5), volatile organic compounds (VOCs), nitrogen oxides (NO_X), sulfur dioxide (SO₂), carbon monoxide (CO) and hazardous air pollutants (HAPs).

Review Documents:

• Original Published Public Notice | View Notice > 
• Revised Permit Application/Modeling Overview | View Revised App. >  
• Orginal Permit Application/Modeling Overview | View App. > 
• Draft Permit | View Permit >  
• Draft Technical Support Document (TSD) | View TSD >
• In person at:
  • ADEQ Record Center | Learn How >
  • Cottonwood City Clerk’s Office, 824 N. Main Street, Cottonwood, AZ 86326

Public Comment Period:

Dates: Sept. 29, 2026 – Nov. 30, 2026

Comments may be submitted as follows:  

• By Email | Send Email >
• By Mail (Must be postmarked or received by Nov. 30, 2026):

ADEQ
Air Quality Division, Air Permits

Attn: Karla Murrieta
1110 W. Washington St.
Phoenix, AZ  85007

• At the Public Hearing in Cottonwood, Arizona | Wednesday, Nov. 18, 2026, 5:30 p.m. | View Details >