In efforts to improve the national emissions inventory of outdoor air toxic sources, which is used for the National Air Toxics Assessment and rule development, the Combined Air Emissions Reporting (CAER) project team researched commonalities and differences between air emissions data submitted and hosted in four databases.
The team developed crosswalks for common data fields in the four systems: chemicals, basis of estimate codes, and waste treatment codes. It also developed recommendations for a Common Emissions Form interface and back-end calculations needed to support combined air emissions reporting for the Toxics Release Inventory (TRI), National Emissions Inventory (NEI), and state, local, and tribal programs.
Staff members from state, local, and tribal environmental agencies and EPA assessed the following:
- Overlaps between TRI and NEI: facilities and pollutants/chemicals covered by both programs, and the quantity of overlapping emissions from these facilities;
- Differences between TRI and NEI: regulatory and programmatic differences, discrepancies in reported emissions quantities for overlapping facilities and pollutants/chemicals (supported by case studies developed to illustrate reasons for such discrepancies);
- Current quality assurance (QA) procedures for each program that involve using other programs’ data (e.g., TRI informed by NEI air emissions, NEI informed by TRI reported air waste streams), from which specific recommendations were developed for improved cross-program QA and data-sharing coordination.
For more information, please contact Julia Gamas of EPA.