An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Knife River Inc. Asphalt Plants, Non-Title V Permit and Technical Support Document

EPA's Non-Title air permits and supporting documents for Knife River Inc. Portable Hot Mix Asphalt Plants at Astec, CMI and Gencor.

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.