Ozone Pollution

Ozone NAAQS Timelines

Key Dates for Existing and Future Nonattainment Areas
	2008 NAAQS	2015 NAAQS
Emission statement rule, emission inventory, and Moderate area/OTR RACT SIPs	July 2014	Late 2019
Marginal area attainment date	July 2015	Late 2020
Attainment plans and demonstrations for initial Moderate areas	July 2015	Late 2020
Attainment plans and demonstrations for initial Serious and above areas	July 2016	Late 2021
Moderate area SIPs for 11 reclassified Marginal areas	Early 2017 (TBD)	--
Moderate area attainment date	July 2018	Late 2023
2008 NAAQS revoked	2018-2019 (TBD)	--

Anticipated Schedule for 2015 Ozone NAAQS Implementation Rules/Guidance/Tools
Action	After NAAQS Promulgation	Planned Dates
Final 2015 Ozone NAAQS revision, monitoring rules, exceptional event demonstration schedule, and PSD permit grandfathering provision	Upon promulgation	October 2015
Propose Exceptional Events Rule revision and guidance on wildfire-related ozone demonstrations	1 month	November 2015
Area designations guidance (including Rural Transport Areas)	4 months	February 2016
Final update to PSD permit modeling guideline (Appendix W; proposed July 2015); MERPs and SIL guidance	8 months	June 2016
Final Exceptional Events Rule revision and guidance on wildfire-related ozone demonstrations	10 months	August 2016
States submit area designation recommendations	12 months	October 2016
Interstate ozone transport contribution assessment provided to States	12 months	October 2016
Propose nonattainment area rules/guidance (including area classifications, SIP due dates, nonattainment NSR provisions)	12 months	October 2016
Final designations, classifications, and nonattainment area SIP rules/guidance	24 months	October 2017
Update to transportation conformity guidance	25 months	November 2017
States submit Infrastructure and Transport SIPs	36 months	Late 2018
States submit attainment plans	5-6 years	2020-2021
Nonattainment Area Attainment Dates (Marginal – Extreme)	5-22 years	2020-2037