This page contains guidance memos to aid states in developing air quality State Implementation Plans (SIPs). The goal of this guidance is to minimize federal and state burden in developing SIPs, while still ensuring the plans' effectiveness in complying with the Clean Air Act. It was developed through collaboration with the National Association of Clean Air Agencies (NACAA/ECOs) SIP Reform Work Group.
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2015 Ozone National Ambient Air Quality Standard - Quick Start Guide for Early Engagement between EPA and Air Agencies (PDF)(11 pp, 1 MB,
February 26, 2019)
This Checklist lays out a sample timeline of key milestones intended to help EPA and state and local air agencies collaborate early and throughout the state implementation plan (SIP) development process for the 2015 8-hour ozone standard.This “early engagement” is a critical component to supporting air agencies in the development of approvable SIPs and EPA in taking timely action on SIPs.
- Regional Consistency for the Administrative Requirements of State Implementation Plan Submittals and Use of "Letter Notices", dated April 6, 2011 (PDF)(13 pp, 3 MB, April 6, 2011)
- Transportation Conformity-related Clarifications to Appendix C of the April 6, 2011 Memorandum, dated July 27, 2011 (PDF)(2 pp, 141 K)
- Options and Efficiency Tools for EPA Action on State Implementation Plan (SIP) Submittals, dated October 31, 2011 (PDF)(15 pp, 128 K)
- Guidelines for Preparing Letters Submitting State Implementation Plans (SIPs) to EPA and for Preparing Public Notices for SIPs, dated November 22, 2011 (PDF)(12 pp, 966 K)