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Request for Coverage Under General Permit for HMA Plants in Indian Country: Knife River Corporation - Mountain West at the Hasselstrom Pit near Winchester, Idaho on the Nez Perce Reservation

On November 13, 2020, EPA Region 10 received from Knife River Corporation - Mountain West a request for coverage under the general air quality permit for new or modified minor source hot mix asphalt plants in Indian Country (HMA General Permit) for a portable plant at the Hasselstrom Pit, Winchester, Idaho on the Nez Perce Reservation.

This application is pending Region 10 review and approval. If you have concerns about the applicant’s eligibility to construct under the HMA General Permit, please contact:

Doug Hardesty (
Air Permits and Toxics Branch
Air and Radiation Division
U.S. Environmental Protection Agency, Region 10
950 W Bannock St, Suite 900
Boise, Idaho 83702

Application Documents

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