Citation:

KLAMSER-WILLIAMS, T., P. A. SOLOMON, P. P. EGEGHY, D. CRUMPLER, J. RICE, J. B. HOMOLYA, AND C. MCDADE. INFLUENCE OF REGIONAL PARTICULATE MATTER ON SELECTED URBAN AREAS ACROSS THE U.S. Presented at American Association of Aerosol Research 2005, Atlanta, GA, February 07 - 11, 2005.

Impact/Purpose:

Develop and evaluate methods for the sampling and analysis of PM in ambient air, with emphasis on FRM/FEM for PMc, measurement of carbonaceous aerosols, measurement of biogenic aerosols, comparisons measurements from the STN and IMPROVE monitoring networks, and continuous methods for PM mass and its chemical components.

Description:

Over the next few years, states will be required to develop state implementation plans for reducing concentrations of fine particles in air where, PM2.5 annual and or daily standards are exceeded. It is now well recognized that high concentrations of PM2.5 in urban areas are in part due to transport of fine particles and particle precursors from upwind locations and that problem is in fact regional, especially in the eastern U.S.. To better understand the sources of PM2.5, the U.S.. EPA has established a national chemical Speciation Trends Network (STN) in urban areas, which provides information on the major and some minor chemical components of PM2.5. This network was initiated in 1999. EPA also has enhanced significantly the number of rural IMPROVE Speciation Monitoring Sites nationally and, combined, these networks provide a fairly comprehensive picture of PM mass and its chemical composition throughout the U.S. To better understand potential differences between the two networks, EPA is evaluating data from an initial comparison of 3 urban-rural sites where collocated samplers from both networks operate based on each network's specific protocols for sampling and analysis. These sites are located in the areas of Washington, D.C., Phoenix, AZ, and Seattle, WA. The sites were chosen to expose the samplers to different ambient chemical and meteorological conditions. This presentation describes the chemical characteristics observed between the urban-rural pairs and the variation of those pairs in different parts of the country during the first year of the study. The regional component, estimated by the rural site, dictates the fraction of the local component that needs to be lowered due to local emissions controls on primary PM and PM precursors and allows for a suggestion of how regional controls may benefit areas out of compliance with current PM standards.

Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy.

Record Details: