Air Plan Approval; TN; Updates to References to Appendix W Modeling Guideline
The Environmental Protection Agency (EPA) is proposing to approve a State Implementation Plan (SIP) revision submitted by Tennessee, on April 9, 2021. Specifically, EPA is proposing to approve updates to the incorporation by reference of federal guidelines on air quality modeling in the Tennessee SIP. Based on its proposal to approve this revision, EPA is also proposing to convert the previous conditional approval regarding infrastructure SIP prevention of significant deterioration (PSD) elements for the 2015 Ozone National Ambient Air Quality Standard (NAAQS) for Tennessee to a full approval. EPA is proposing to approve this revision pursuant to the Clean Air Act (CAA or Act).