PM2.5 Implementation Rule- Modeling Summary. Brian Timin EPA/OAQPS [email protected] June 20, 2007. Attainment Demonstrations. CAA Section 172(c) requires States with a nonattainment area to submit an attainment demonstration
*We expect the attainment test for the new 24-hr PM2.5 standard to be the same or similar to the procedures in the current version of the modeling guidance. As part of the implementation process for the revised standard, the procedures in the guidance will be re-evaluated.