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Timeline for Implementing the 24-hour PM2.5 Standard
| Milestone | Deadline |
|---|---|
| Promulgation of Standard | Sep. 21, 2006 |
| Effective Date of Standard | Dec. 18, 2006 |
| State Recommendations to EPA | 1 year after new standard – Dec. 18, 2007 (based on 2004 - 2006 monitoring data) |
| Final Designations Signature | 2 years after new standard – Dec. 22, 2008 (based on 2005 - 2007 monitoring data). This notice never became effective and was reviewed by the new Administration. – October 2009 (based on 2006 - 2008 monitoring data) |
| Effective Date of Designations | 30 days after publication in the Federal Register – likely November 2009 |
| SIPs Due | 3 years after effective date of designations – likely November 2012 |
| Attainment Date | No later than 5 years after effective date of designations – likely November 2014 |
| Attainment Date with Extension | No later than 10 years from effective date of designations – likely November 2019 |