Technology Transfer Network - Air Toxics Web Site
Notice of Source Category Listings for the Specific Pollutants (Section 112(c)(6))
WHAT IS SECTION 112(c)(6)?
Section 112(c)(6) of the Clean Air Act Amendments (CAAA) of 1990 requiresthat the EPA identify sources of alkylated lead compounds, polycyclicorganic matter (POM), mercury, hexachlorobenzene, polychlorinatedbiphenyls(PCB), 2,3,7,8-tetrachlorodibenzofurans (TCDF) and2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). These identified sources willaccount for not less than 90% of the aggregate emissions of each pollutantsubject to standards under Subsection 112(d)(2) or 112(d)(4). Standardsmust be developed for sou rces of these hazardous air pollutants (HAPs) by EPA not later than ten years after the date of enactment.
TODAY'S ACTION (4-3-98)
The Environmental Protection Agency (EPA) is today issuing a list of additional industry groups (known as "source categories") that emit seven specific hazardous air pollutants; namely, alkylated lead compounds, polycyclic organic matter (POM), hexachlorobenzene, mercury, polychlorinated biphenyls, 2,3,7,8-tetrachlorodibenzofurans (TCDF) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Hazardous air pollutants are also known as air toxics; these are pollutants which are known or suspected to cause cancer or other serious health effects such as birth defects or reproductive effects.
The Clean Air Act Amendments of 1990 required EPA to identify the sources of 90 percent of the emissions of each of these seven specific pollutants. Further, the Act requires EPA to subject these sources to technology-based standards (under section 112(d)(2), known as maximum achievable control technology or MACT) or determine that their emissions do not violate established health thresholds (under section 112(d)(4)).
A review of the available data indicates that a substantial majority of source categories emitting the seven pollutants have already been listed for regulation under another section of the Clean Air Act (section 112(d)(2)) or are subject to comparable regulation under other Clean Air Act authorities. Consequently, EPA is issuing a list of only two additional source categories in response to the requirement to ensure that 90 percent of the emissions of the seven pollutants has been targeted for regulation: (1)Open Burning of Scrap Tires and (2)Gasoline Distribution Stage I Aviation, includes evaporative losses associated with the distribution and storage of aviation gas containing lead
HOW DID EPA EVALUATE THE SOURCES OF THE SEVEN POLLUTANTS?
In order to determine the sources of the seven air toxics,
EPA developed emission inventories of known sources of each pollutant.
Emissions inventories consist of estimates of annual emissions to the
air from all sources (with available data) such as power plants, chemical
plants, automobiles, and forest fires. Using this inventory data, EPA
identified the sources of the total emissions of these seven
pollutants. However, EPA did not further evaluate certain types of sources
that could not appropriately be addressed under the authorities of section
112 of the Clean Air Act. These excluded sources are wildfires and prescribed
burning, mobile sources (cars, airplanes, etc.), residential combustion
sources (fireplaces, woodstoves, oil and coal heaters), pesticide application,
cigarette smoke, utility boilers, gasoline distribution stage II (evaporative
emissions from gas stations), and consumer products usage. The EPA evaluated
the remaining categories of sources to determine whether they were currently
regulated or scheduled for regulation under sections 112(d)(2) or (d)(4).
BACKGROUND
Under the Clean Air Act Amendments of 1990, EPA is required to regulate sources of listed toxic air pollutants. On July 16, 1992, EPA published a list of industry groups (known as source categories) that emit one or more of these air toxics. For listed categories of "major" sources (those that emit 10 tons/year or more of a listed pollutant or 25 tons/year or more of a combination of pollutants), the Clean Air Act requires EPA to develop standards that require the application of stringent air pollution reduction measures known as maximum achievable control technology (MACT).
Section 112(c)(6) of the Clean Air Act requires EPA to identify the source categories that emit 90 percent of the aggregate emissions for each of the seven specific pollutants and add any source categories not previously identified to the list discussed above.
These seven pollutants [alkylated lead compounds, polycyclic organic matter (POM), hexachlorobenzene, mercury, polychlorinated biphenyls, 2,3,7,8-tetrachlorodibenzofurans (TCDF) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)] were among the pollutants of concern identified by the International Joint Commission of the United States and Canada, and the Great Lakes Commission, as well as EPA's Great Waters Program because of their persistence and tendency to bioaccumulate in the environment. These pollutants are also associated with adverse health effects such as nervous system damage and reproductive effects.
The EPA is not planning to list some source categories that contribute to emissions of the seven pollutants because these sources are subject to another equivalent authority of the Clean Air Act. These sources include medical and municipal waste emissions which are regulated under EPA's solid waste combustion standards and combustion sources included in EPA's on-going effort to develop the Industrial Combustion Coordinated Rulemaking. The EPA believes additional regulation could lead to a redundant regulatory effort with little or no additional environmental benefit.
WHAT SOURCE CATEGORIES IS EPA LISTING?
A review of the available data indicates that a substantial
majority of source categories emitting the seven pollutants have already
been listed for regulation under section 112(d)(2) or are subject to comparable
regulation under other authorities. As a result, EPA is issuing a list
of only two additional source categories to satisfy the requirements of
section 112(c)(6):
Open Burning of Scrap Tires
Gasoline Distribution Stage I Aviation, includes evaporative
losses associated with the distribution and storage
of aviation gas containing lead
The EPA is required to promulgate regulations developed for any of these additional source categories by November 15, 2000 (under section 112(d)(2) authority).
FOR MORE INFORMATION
Interested parties can download the Federal Register notice and the emissions inventory documentation below. The notice and background documentation is also available through EPA's Air and Radiation Docket and Information Center (Docket Number A-97-05) by calling (202) 260-7548 or -7549 or FAX (202) 260-4000 (a reasonable fee may be charged for copying). For technical questions about this action, contact Laurel Driver (919) 541-2859. The EPA's Office of Air and Radiation Web Site contains a wide range of information on the air toxics program, as well as many other air pollution programs and issues.
The following documents can be downloaded in WordPerfect® formator Adobe Acrobat® format. For assistance with downloading thesefiles, call the InfoCHIEF Help Desk at (919)541-5285.
| Document Title | Files |
| Section 112(c)(6) Federal Register Notice |
 253 KB |
| 1990 Emissions Inventory of Section 112 (c)(6) Pollutants:
Final Report |
702 KB |
| 1990 Emissions Inventory of Section 112 (c)(6) Pollutants:
Final Report - Appendix A |
404 KB |
| 1990 Emissions Inventory of Section 112 (c)(6) Pollutants:
Final Report - Appendix B |
227 KB |
| 1990 Emissions Inventory of Section 112 (c)(6) Pollutants:
Final Report - Appendix C |
73 KB |
| Summary of Public Comments on the 112(c)(6) Draft Listing Notice |
84 KB |
Comments and all questions about the Specific Pollutants (Section112(c)(6)) Final Listing should be directed to:
Ms. Laurel Driver
Visibility and Ecosystem Protection Group
U. S. EPA, Mail Drop 15
Research Triangle Park, NC, 27711
Phone: (919) 541-2859
Email: driver.laurel@epamail.epa.gov