Data and Information Management
In addition to data collected for permit fee billing purposes, the Data and Information Management Branch, in cooperation with the Mobile, Smoke, and Area Sources Branch, also collects and prepares emissions data annually for the National Emissions Inventory (NEI) of the US EPA. These data are used by the US EPA and the NDEP for statewide and regional studies, assessing program effectiveness, and other planning purposes.
EPA's Emission Inventory and Analysis Group (EPA/OAR/OAQPS/AQAD/EIAG) prepares a national database of air emissions information with input from numerous state and local air agencies, from tribes, and from industry. This database contains information on stationary and mobile sources that emit criteria air pollutants and their precursors, as well as hazardous air pollutants (HAPs). The database includes estimates of annual emissions, by source, of air pollutants in each area of the country, on an annual basis.
Data from the NEI are used for air dispersion modeling, regional strategy development, regulation setting, air toxics risk assessment, and tracking trends in emissions over time. For emission inventories prior to 1999, criteria pollutant emission estimates were maintained in the National Emission Trends (NET) database and HAP emission estimates were maintained in the National Toxics Inventory (NTI) database. Beginning with 1999, criteria and HAP emissions data were prepared in a more integrated fashion in the National Emissions Inventory (NEI), which takes the place of the NET and the NTI.