Emissions Inventories

The Emission Inventory Branch of the Air Division develops and manages air emission inventories for air quality planning, analysis and permitting. An air emission inventory represents the type and amount of air contaminants that are released from different sources. Several different types of inventories are maintained for these purposes.

Point Source Inventories

Emissions from major commercial and industrial sources, also referred to as point sources, are quantified when facilities are permitted. The Air Division maintains an inventory of these emissions in a database and provides this information for Prevention of Significant Deterioration of Air Quality (PSD) modeling and other air quality analysis purposes.

To request inventory information for PSD modeling, please contact a member of the Emissions Inventory Group.

The following information will be needed:

  • Site latitude/longitude coordinates
  • Site address
  • Radius of inventory
  • Pollutants that are needed
  • When the inventory is needed
  • Your name and phone number

Emissions Reporting- Consolidated Emissions Reporting Rule (CERR)

Every year MDEQ is required by EPA to report actual air emissions for Title V facilities that are considered super-major sources. The actual emission thresholds for super major source determination is 2500 tons per year of Carbon Monoxide (CO), Nitrogen Oxides (NOx) or SO2 and 250 tons per year of Particulate Matter (PM) or Volatile Organic Compounds (VOC). If the facility meets or exceeds these limits then they are required to complete the CERR every year. If the facility doesn’t meet these criteria then it is required to submit a CERR every 3 years. The next CERR for all Title V facilities will be for the 2008 operating year. A request will be mailed out in April of the subsequent year. For more information about the CERR contact the emission inventory group.

Mobile and Area Source Inventories

The Air Division develops an inventory of emissions from cars, trucks, boats, construction equipment and other non-stationary equipment, referred to as mobile sources, and minor commercial facilities and residences, referred to as area sources. While these sources of emissions are not directly regulated by the Department of Environmental Quality, they can have a significant impact on air quality.

Other Links

Air Pollutant Emission Trends - EPA emissions summaries and reports for the entire United States
AIRData webpage -EPA detailed air emissions data, reports and maps in a user specified format. (*Note: County level information Mississippi, as well as other states, can be obtained here.)
Office of Transportation and Air Quality - EPA information on mobile emissions sources


To contact MDEQ staff for further information on Emissions Inventories click here.