Receptor Modeling Applications for State Implementation Plans
Project Leads and Affiliations:
Rachelle Duval, EPA/Office of Research and Development
Dr. Donna Kenski, Lake Michigan Air Director's Consortium/Midwest Regional Planning Organization
Michael Davis and Bret Anderson, EPA Region 7
Terry Rowles and Calvin Ku, State of Missouri
Project Abstract Written: October 2005
Project Timeframe: 2006 - 2008
In 2004 EPA designated non-attainment areas for the 1997 PM NAAQS. States with areas designated to be in non-attainment are required to submit State Implementation Plans (SIPs) that describe how they will meet the requirements of the NAAQS. A critical piece of a SIP is identification of sources contributing to air pollution so that effectively targeted control strategies can be developed. Identification of sources for the 1997 PM NAAQS is unlike identification for sources for previous NAAQS. First, local sources are believed to be significant contributors to PM in many airsheds. Simulation models have been the classic tool for SIP development; however, these models are not effective at modeling local scale air quality. As a result, other approaches such as receptor modeling will be critical for developing SIPs. Second, it generally is the annual PM standard that is being violated, thus interest is in annual contributions of sources, not contributions of sources on extremely high days. Quantifying annual contributions requires quantifying contributions from all seasons which generally means quantifying low contributions as well as high contributions. These two reasons mean techniques for identification and quantification of sources, especially local ones and ones with possibly low contributions, are needed to develop effective control strategies that lead to improved air quality.
The objective of this project is to develop such techniques for St. Louis, a PM non-attainment area. The project will apply emerging modeling tools to advanced monitoring data from the St. Louis Supersite and to routinely collected data to identify sources of PM contributing to St. Louis' non-attainment status. Products will include a document detailing the annual and seasonal average contributions from sources impacting receptors in St. Louis, with emphasis on local sources, and a document describing techniques used and types of data that best aid in the identification and quantification of sources, a document that should be useful for designing future data collection activities or analyzing data at other locations for SIP support. As the technical work for the St. Louis SIP needs to be completed by early winter, progress can readily be measured by how the results from this proposal contribute to that SIP.