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Second Report to Congress on the Status of the Program to Reduce Emissions of Hazardous Air Pollutants Under the Clean Air Act

SECOND REPORT TO CONGRESS ON THE STATUS OF THE PROGRAM TO REDUCE EMISSIONS OF HAZARDOUS AIR POLLUTANTS UNDER THE CLEAN AIR ACT (EPA-453/R-96-015), October 1997.


This status report is in response to the requirements of section 112(s) of the CAA of 1990, in
which Congress has requested the Administrator to "prepare and transmit to the Congress a
comprehensive report on the measures taken by the Agency and by the States to implement the
provisions of this section."  "The report shall include, but not be limited to -

      (1) a status report on standard-setting under subsections(d) and (f);

      (2) information with respect to compliance with such standards including the costs of
     compliance experienced by sources in various categories and subcategories;

      (3) development and implementation of the national urban air toxics program; and

      (4) recommendations of the Chemical Safety and Hazard Investigation Board with respect
     to the prevention and mitigation of accidental releases."

This report is the second section 112(s) Report to Congress. It is formatted differently from the first section 112(s) Report to Congress, EPA/453/R-93-024, dated August 1993. The first report documented individual standards, studies, and a number of programs called for under section 112. The current report addresses, in Section III, the four topics specifically requested by the 1990 CAA, including the infrastructure needed to carry out these programs. Additionally, the report discusses in Section IV, achievements made in the regulation of Solid Waste Combustion under Section 129.


The document, Second Report to Congress on the Status of the Hazardous Air Pollutant Program under the Clean Air Act, (EPA-453/R-96-015), October 1997, is available for download in Portable Document Format (PDF). For information on file formats, see TTNWeb File Types.


For further information about the report, please contact Teresa Clemons, (clemons.teresa@epamail.epa.gov) of EPA's Office of Air Quality Planning and Standards.

ADDITIONAL INFORMATION
Key Findings

Between 1970 and 1990, the Clean Air Act required the Environmental Protection Agency (EPA) to employ a risk-based approach to setting emission standards for hazardous air pollutants (also known as air toxics). Unfortunately, under this approach EPA was only able to set standards for seven hazardous air pollutants during this time frame. However, this work did establish a strong foundation for future risk-based work on air toxics.

Since 1990, EPA has made use of a performance-based approach to setting emissions standards. The performance-based approach requires EPA to set standards based on consideration of those controls present at the best controlled facilities within an industry. Under this approach EPA has promulgated standards for 47 categories of industrial sources of air toxics. When fully implemented, these emission standards will reduce air toxics emissions by approximately 980,000 tons/year.

Background

As required by section 112(s) of the Clean Air Act, EPA is transmitting the second triennial Report to Congress on the Status of the Hazardous Air Pollutant Program under the Clean Air Act. Hazardous air pollutants (also known as air toxics) are pollutants which are known or suspected to cause cancer or other serious health effects such as birth defects or reproductive effects. This report provides information on several EPA Programs that aim to control emissions of air toxics. Specifically, this report comments on:

  • The status of EPA's program to set emission standards for air toxics. EPA is required to establish standards for so-called "major" and "area" sources of the 188 air toxics listed in the Clean Air Act Amendments of 1990. Major sources are stationary sources that have the potential to emit 10 tons/year or more of a listed hazardous air pollutant or 25 tons/year of or more of a combination of pollutants. Area sources are stationary sources that emit hazardous air pollutants, but are not classified as a major source.
  • The compliance issues associated with these emissions standards including the costs incurred by regulated industries and other sources.
  • The development and implementation of the national urban air toxics program.
  • The recommendations of the Chemical Safety and Hazard Investigation Board with respect to the prevention and mitigation of accidental releases of air toxics.
  • A summary of solid waste combustion regulatory activities which will reduce air toxic emissions.

Prior to the passage of the 1990 Clean Air Act Amendments, EPA utilized a risk-based system to determine regulations for air toxics. Because of the lack of data linking exposure to specific hazardous air pollutants to specific health effects, sole reliance on a risk-based system made it difficult to develop emission standards. In fact, between 1970 and 1990, EPA was only able to set standards for seven hazardous air pollutants. However, it is important to note that the work done between 1970 and 1990 did help EPA establish a strong foundation for future risk-based work on air toxics.

In 1990, Congress acknowledged the difficulty of relying on this risk-based approach and replaced it with a performance-based approach. The performance-based approach requires EPA to set standards based on consideration of those controls present at the best controlled facilities within an industry. The goal of this approach is to successfully reduce emissions of air toxics.

As part of this new approach, Congress listed a number of hazardous air pollutants that EPA believes cause adverse health or environmental effects, established a clear method for developing performance-based standards for the sources of those air toxics, and set a detailed ten-year schedule for action.

These standards are know as Maximum Achievable Control Technology (MACT) standards. The ten-year schedule required that certain standards be promulgated in the first 2 years, approximately 25 percent in the first 4 years, an additional 25 percent promulgated not later than the 7th year, and the remaining 50 percent not later that the 10th year.

Progress

To date, this program has been productive in fulfilling the 2 and 4 year MACT statutory requirement. This new performance-based approach to standard setting has resulted in measurable progress and has confirmed the judgement of Congress in moving away from strict reliance on the risk-based system.

Since 1990, EPA has promulgated standards for all of the 47 categories of industrial sources (known as "source categories") in the 2-year and 4-year groups. These source categories make up approximately 25 percent of the 174 source categories listed under the program.

Benefits

EPA estimates that, when fully implemented, the standards promulgated to date will reduce air toxic emissions by approximately 980,000 tons/year. They will also help control so-called "criteria" pollutants (e.g. particulate matter or pollutants that cause smog), some of which are air toxics, amounting to approximately 1,810,000 tons/year.

Given the appropriate resource funding, this program will continue to achieve emission reductions through the MACT program when EPA issues standards required for 1997 and 2000. EPA is actively working on developing and proposing many of these standards. Further, the MACT program will identify and implement needed future emission reduction goals through several investigatory studies that EPA is currently conducting, including the urban area source studies and strategy development, the mercury study, the great waters study, and the utility study.

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