EPA’s “Guidance on New R-LINE Additions to AERMOD 19191 for Refined Transportation Project Analyses” is now final and available online at: https://www.epa.gov/state-and-local-transportation/project-level-conformity-and-hot-spot-analyses
A direct link to the guidance: https://www.epa.gov/sites/production/files/2019-09/documents/420b19042.pdf
On August 21, 2019, EPA released a new version of its preferred dispersion model, AERMOD 19191. AERMOD 19191 builds upon the previous version of AERMOD, AERMOD 18081, and adds new features from EPA’s R-LINE model. Information about AERMOD and this latest release can be found on EPA’s website at: https://www.epa.gov/scram/air-quality-dispersion-modeling-preferred-and-recommended-models. This guidance is part of the resources EPA is providing with the release of AERMOD 19191. It addresses the use of the new R-LINE features in AERMOD 19191 for dispersion modeling of transportation sources.