Dispersion modeling may be required by regulatory agencies when industrial facilities undertake physical expansions or increases in production rates. The modeling is used to demonstrate that the facility will comply with ambient air quality standards (AAQS). The standards are periodically reviewed and revised by regulatory agencies, as are the dispersion models themselves and guidance for their use. It may have been many years since a facility has conducted modeling, or the facility may never have been required to model. Modeling demonstrations can be a time-consuming element of a permitting project.
At five ethanol production facilities located in three midwestern states, Barr was hired to conduct preliminary dispersion modeling for coarse particulates (PM10), fine particulates (PM2.5), and nitrogen dioxide (NO2). The modeling was not required by any agency at the time of the project but was conducted to identify sites and sources that may pose a challenge to demonstrating compliance with AAQS when future projects are pursued and to get a head start on identifying potential model refinements that would address the issues. A culpability analysis of the results was developed to identify the critical sources and focus the refinements. The analysis allowed our client to plan for projects that would require additional measures to meet AAQS.
Air Quality Scientist
Senior Air Quality Consultant
Vice President Senior Environmental Consultant