ENV-11-47 Effect of New NAAQS Air Dispersion Modeling Requirements on the Petroleum Refining Industry

Description:

EPA recently promulgated new 1-hour NO2 and SO2 National Ambient Air Quality Standards (NAAQS) and changed the procedures for evaluating PM2.5 emissions from industrial facilities for comparison with the PM2.5 NAAQS. These changes are expected to have a dramatic effect on New Source Review (NSR) permitting of new and modified facilities within the refining industry sector, particularly in urban areas with high background levels of these pollutants and in rural locations where a cluster of similar facilities are located in the same general area. In such areas, the ability to expand or modify facilities may be greatly restricted as a result of the new standards and guidelines. A brief summary of the new standards and guidelines will be presented, followed by a discussion of the most problematic aspects of demonstrating compliance with the new standards, including increased numeric stringency, overly conservative EPA guidance, high ambient background levels, lack of adequate source inventories in many states, and model limitations. Examples are provided of both real and hypothetical facilities to illustrate the magnitude of the issues created by the new requirements and identify the most problematic geographic areas in the U.S. for dealing with them. Recommendations are provided for refining the air quality modeling analyses to reduce predicted impacts, and strategies for streamlining the modeling process are presented.