U.S. EPA's Support Center for Regulatory Air Models

U.S. EPA's Support Center for Regulatory Air Models- The U.S. Environmental Protection Agency uses this site to provide information on the many dispersion models supporting regulatory programs required by U.S. law. All of the EPA's dispersion models and their Users' Manuals can be downloaded cost-free from here. An online forum is also provided for discussion/questions/answers on all aspects of the EPA's models.