EPA regulates hazardous air pollutants under Section 112 of the Clean Air Act. Hazardous air pollutants are known or suspected to cause serious health problems such as cancer. They are also known as toxic air pollutants or, simply, air toxics. They may present either chemical or radioactive hazards. EPA regulations established under Section 112 are known as National Emission Standards for Hazardous Air Pollutants (NESHAPs).

EPA has promulgated standards for a number of hazardous air pollutants, including radionuclides. Within the radionuclide category, EPA has established individual standards for eight source categories: Underground Uranium Mines (Subpart B); Department of Energy Facilities (Subpart H); Certain Non-DOE Federal Facilities (Subpart I); Elemental Phosphorous Plants (Subpart K); DOE Facilities Radon Emissions (Subpart Q); Radon from Phosphogypsum Stacks (Subpart R); Non-Operational Uranium Mill Tailings Piles (Subpart T); and Operating Uranium Mill Tailings Piles (Subpart W).

The general provisions of 40 CFR Part 61 apply to all NESHAPs (including both chemical and radiation hazards) and prohibit certain activities, including:

• Constructing or modifying a stationary source without prior written approval from EPA;
• Operating a new stationary source in violation of the applicable NESHAP;
• Operating an existing stationary source in violation of the applicable NESHAP; and
• Failing to report.

You can find more information about NESHAPs in general on the Unified Air Toxics Web Site. To find specific information about the NESHAP for a specific radiation source category, click on the following links:

• Subpart B: Underground Uranium Mines
• Subpart H: Department of Energy Facilities
• Subpart I: Certain Federal Facilities
• Subpart K: Elemental Phosphorus Plants
• Subpart Q: Department of Energy Radon Emissions
• Subpart R: Radon from Phosphogypsum Stacks
• Subpart T: Disposal of Uranium Mill Tailings
• Subpart W: Operating Uranium Mill Tailings Piles