EPA continues to update SPECIATE, the U.S. Environmental Protection Agency's (EPA) repository of chemical speciation profiles of many types of air pollution sources. This presentation discusses the most recent improvements to the SPECIATE program, culminating in one of the quickest-ever releases of the updated version, SPECIATE 5.1, on July 20, 2020. It also reviews the profiles of importance for use emissions platforms used for air quality modeling. The updated version, SPECIATE 5.1, was completed about a year after SPECIATE 5.0. For this update, 92 total profiles (16 organic gas, 18 particulate matter and 58 mercury profiles) were added to the database. These improvements will assist the user community with PM, VOC, and mercury species characterization related, primarily, to oil and gas (VOC), fires (PM) and geothermal power (Hg). The release also includes improvements to the database structure, species properties information and interface with the Speciation Tool. Finally, we have completed updates to the Web Browser and added a browser’s user’s guide as well as a data developer’s guide, providing the structure for how submitters can submit/prepare data for SPECIATE use. For the first time, our Data Developer’s Guide/Template was used for community-developed data submission to SPECIATE. The SPECIATE Workgroup continues seek new data for future versions of SPECIATE. Priorities for profile sources have been presented in previous AWMA conferences and include region-specific oil and gas profiles for VOC, fires profiles for VOC and PM2.5, open burning for VOC and residential wood combustion profiles for VOC. We will review these profile priorities and identify other source categories for which updated speciation would improve our estimates of air toxics in the NEI.
