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Approved Air Quality Implementation Plans in Region 8

This site contains information about air quality regulations called State Implementation Plans (SIPs), Federal Implementation Plans (FIPs), and Tribal Implementation Plans (TIPs) approved by EPA Region 8.

State Implementation Plans

Approved regulations, sources specific requirements, and non-regulatory provisions.

EPA-approved regulations and planning documents.  

Federal Implementation Plans

Tribal Implementation Plans

Region 8 currently has no approved TIPs.


About this website: The official SIPs, TIPs, and FIPs are contained in regulations promulgated in the Federal Register and codified in the U.S. Code of Federal Regulations (CFR).  EPA’s web-versions of the approved SIPs, TIPs, and FIPs are for reference.  While we make every effort to maintain the accuracy of the files accessible here, inconsistencies may occur.  Please contact us using the link below if you find any errors in these files.