What is an Area Source of Hazardous Air Pollutants? Why is it regulated?

Hazardous air pollutants (HAPs) are known or suspected to cause adverse environmental effects and/or serious health effects. The U.S. Environmental Protection Agency (EPA) has identified 187 air pollutants, for example, benzene, which is found in gasoline. EPA places standards, or requirements on categories of stationary sources that emit (or have the potential to emit) one or more hazardous air pollutants called national emission standards for hazardous air pollutants (NESHAP) standards. EPA lists these standards and which agency enforces the standards in tables published in the Federal Register.

Major source of hazardous air pollutants: The term "major source"  refers to any stationary source or group of stationary sources that emits or has the potential  to emit 10 tons per year of any of the 187 named pollutants, or 25 tons per year of a mixture of pollutants.

Area source of hazardous air pollutants: The term "area source" refers to facilities that release smaller quantities of toxic air pollutants. Although emission from one area source may be relatively small, multiple area sources concern environmental specialists, especially when they are in densely populated areas.

To reduce the hazardous area pollutants released by area sources, EPA places standards, or requirements, on area sources to minimize emissions. These requirements call for specific management practices and generally available control technologies (GACT). These technologies consist of methods, practices, and techniques applicable to area sources. When EPA developed these technologies, staff members considered the economic impact as well as the technical abilities of employees to operate and maintain systems for emission control.

What are Missouri's Area Source Requirements?

The following table gives area source requirements for which the Missouri Department of Natural Resources is conducting compliance-enforcement activities. Direct questions regarding standards, compliance, and reports about area sources to the agency listed as “Regulating Agency” in the table, below. The department's Air Pollution Control Program recommends that facilities submit notifications and other required reports about area sources to the air program and EPA Region 7 contacts. If you have questions regarding any of the area source regulations or need help navigating the requirements, contact the Air Pollution Control Program.

Dry Cleaners

Online Compliance Resources for Missouri Area Source Requirements

Regulating Agency Description Sort descending 40 CFR 63 Subpart Title V Permit Keywords Rule and Implementation Information Regulation Helpful Link
MoDNR Hazardous Waste Incineration Regulations (Major and area sources) (3E) - EEE Major Permit hazardous waste Link Link
EPA Hospital Ethylene Oxide Sterilizers (5W) - WWWWW Exempt hospital Link Link
EPA Industrial, Commercial and Institutional Boilers (6J) - JJJJJJ Exempt Boilers Link Link Link
EPA Iron and Steel Foundries (5Z) - ZZZZZ Exempt Foundry Link Link
EPA Lead Acid Batteries Industry (6P) - PPPPPP Exempt lead Link Link
MoDNR Marine Tank Vessel Loading Operations (Major and new area sources) (1Y) - Y Major Permit Vessel Link Link
MoDNR Mercury Cell Chlor-Alkali Plants (Major and area sources) (5I) - IIIII Major Permit Mercury Cell Chlor-Alkali Link Link
MoDNR Municipal Solid Waste Landfills (Major and area sources) (4A) - AAAA Major Permit landfill Link Link Link
EPA Nine Metal Fabrication and Finishing Source Categories (6X) - XXXXXX Exempt Metal Fabrication and Finish Link Link Link
MoDNR Oil and Natural Gas Production Facilities (Major and area sources) (2H) - HH Exempt Oil and Natural Gas Link Link
EPA Paint Stripping and Miscellaneous Surface Coating Operations (6H) - HHHHHH Exempt Paint Link Link Link
EPA Paints and Allied Products Manufacturing (7C) - CCCCCCC Exempt Paint Link
EPA Plating and Polishing Operations (6W) - WWWWWW Exempt Plating and Polishing Link Link Link
EPA Polyvinyl Chloride and Copolymers Production (6D) - DDDDDD Exempt Polyvinyl Chloride Link Link
MoDNR Portland Cement Regulations (Major and area sources) (3L) - LLL Major Permit Cement Link Link
EPA Prepared Feeds Manufacturing (7D) - DDDDDDD Exempt animal feed Link Link Link
EPA Primary Copper Smelting (6E) - EEEEEE Major Permit Copper Link
MoDNR Primary Lead Smelting (3T) - TTT Major Permit lead Link Link
EPA Primary Nonferrous Metals Area Sources—Zinc, Cadmium, and Beryllium (6G) - GGGGGG Major Permit zinc, Cadmium, beryllium Link
MoDNR Printing and Publishing Industry (Some Major sources that can prove actuals below HAP limits) (2K) - KK Major Permit Printing Link Link