Preparation of the 2005 Point Sources National Emissions Inventory

Every three years, the U.S. Environmental Protection Agency (EPA) prepares the National Emissions Inventory (NEI), an air quality emissions inventory dataset that serves numerous stakeholders, including federal, regional, state, local, and tribal agencies. Uses of the NEI data include: evaluating emission trends; preparing inputs for air quality modeling; and evaluating the need for additional control technology standards. The NEI consists of stationary, mobile, and biogenic emission sources. Stationary sources can be classified as point or nonpoint area sources, whereas mobile sources are categorized as onroad or nonroad sources. At present, the NEI houses criteria and hazardous air pollutants. The purpose of this paper is to describe the compilation of the point sources portion of the 2005 NEI. A number of data sources, augmentation techniques, and quality assurance checks were used to prepare the point sources inventory. Over 70 datasets from federal, state, local, tribal, and regional air agencies were the primary basis for the national inventory. Emissions, locational coordinates, and stack parameter data from EPA’s Risk and Technology Review Program are also considered a primary data source, as these high quality data have been peer-reviewed by numerous state agencies, industry, and trade associations. Additionally, EPA datasets from the Emission Inventory and Analysis Group, the Sector Policies and Programs Division, the Toxic Release Inventory, and version 3 of the 2002 NEI are blended and merged with the above primary data sources for source category and geographic completeness. Finally, emissions data from offshore oil and gas platforms operating in the Gulf of Mexico were included from the Minerals Management Services