Air dispersion modeling may be required in some instances to demonstrate with National Ambient Air Quality Standards (NAAQS) and/or local ambient air regulations. Typically, ACES' documentation begins with descriptions of the source(s), existing air quality at the site, and the source characteristics, including the emission rates, stack or release point parameters, and consideration of potential building wake effects. Modeling protocol will be defined and will address the selection of an appropriate, EPA-approved model or models and/or local regulators agency meteorological data, receptor placement, and model options (terrain, wind profile, downwash considerations, etc.).
The modeling results and air quality impacts are discussed and summarized in tabular form and appendices contain copies of the actual printouts of the model's computer runs. In addition to the above documentation, ACES also supplies computer discs containing all of the air dispersion modeling files for submittal to the appropriate regulatory agency as part of the air permit application. ACES staff has successfully conducted numerous air quality dispersion modeling projects that have supported clients' air permit applications.