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Technology Transfer Network - OAR Policy and Guidance






  • On June 20, 2005 the Environmental Protection Agency (EPA) proposed to reconsider certain aspects of its final national emissions standards to control hazardous air emissions from industrial, commercial, and institutional boilers and process heaters. EPA promulgated the final rule on September 13, 2004. The June 20 boilers reconsideration notice is posted at https://www3.epa.gov/ttn/oarpg/t3pfpr.html.

  • Boilers burn fossil fuel (coal, gas and oil) and/or other biomass substances such as wood and agricultural residues to produce steam. The steam is used to produce electricity or provide heat. Process heaters heat raw or intermediate materials during an industrial process. Boilers and process heaters are used at facilities such as refineries, chemical and manufacturing plants, and paper mills. In addition, these boilers may stand alone to provide heat for shopping malls and university heating systems.

  • Following promulgation of the final rule, the EPA Administrator received petitions for reconsideration filed by the Natural Resources Defense Council (NRDC) and Environmental Integrity Project (EIP).

  • The petitions collectively requested reconsideration of the following aspects of the final rule:

    1. adoption of "no control" maximum achievable control technology (MACT) levels for certain subcategories and pollutants;
    2. establishing risk-based alternatives on a plant-by-plant basis;
    3. presence of health thresholds for hydrogen chloride (HCl) and manganese;
    4. consideration of background pollution and co-located emission sources;
    5. establishing a health-based compliance alternative for a pollutant (HCl) that serves as a surrogate for other inorganic pollutants;
    6. promulgating a health-based compliance alternative that allows low-risk sources of manganese emissions to comply with the MACT limitations for metals without counting manganese; and
    7. the procedures for demonstrating compliance with the health-based alternatives.
    8. consideration of emissions during periods of startup, shutdown, and malfunction
    9. the cost-effectiveness of the health-based alternatives

  • NRDC and EIP also requested a stay of the health-based compliance alternatives.

  • In this notice, EPA is granting reconsideration on several issues raised in the joint NRDC/EIP petition for reconsideration and requesting public comment on certain issues regarding the health-based compliance alternatives . The notice also provides opportunity for a public hearing. How to comment.

  • EPA is requesting comment on the approach used to demonstrate eligibility for the health-based compliance alternatives, as outlined in Appendix A of the final rule, and on the provisions establishing a health-based compliance alternatives for total selected metals.

  • Although EPA believes these aspects of the final rule are properly supported and justified, we are re-opening them to additional public input. EPA is not requesting comment on any other provisions of the final rule.

  • EPA is not granting the petitioner's request for a stay of the health-based compliance alternatives.

  • This notice also includes two technical corrections to clarify an implementation issue.

  • Comments may be submitted for 45 days following publication of the reconsideration notice in the Federal Register .

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  • Under the Clean Air Act, EPA is required to regulate emissions of 188 specific air toxics. 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 have the potential to emit 10 tons per year or more of a single listed air toxic or 25 tons per year or more of a combination of air toxics), the Clean Air Act requires EPA to develop standards that restrict emissions to levels consistent with the lowest-emitting (also called best-performing) facilities. These standards are based on stringent air pollution reduction measures known as maximum achievable control technology (MACT).

  • The EPA's published list of industry groups to be regulated includes "Industrial Boilers," "Commercial and Institutional Boilers," and "Process Heaters." Standards for these source categories were jointly proposed on January 13, 2003 and promulgated on September 13, 2004.

  • The final rule included health-based compliance alternatives for threshold pollutants based on section 112(d)(4) of the Clean Air Act. Eligible sources that meet the rule's health-based compliance alternatives are considered in compliance with the emission standards. Eligibility for the health-based compliance alternatives is determined under Appendix A of the final rule which is entitled "Methodology and Criteria for Demonstrating Eligibility for the Health-Based Compliance Alternatives."

  • The final rule provides two ways a facility may demonstrate that a boiler or process heater qualifies for the health-based compliance alternative.

    1. "Lookup tables" - listed in the rule - allow facilities to use a limited number of site-specific input parameters to determine whether emissions from boilers or process heaters might cause a hazard index limit for non-carcinogens to be exceeded.

    2. Facilities may demonstrate by modeling, using site-specific information that emissions of threshold pollutants such as HCl, chlorine, or manganese from the boiler or process heater under evaluation do not cause a hazard index limit to be exceeded.

  • Facilities that demonstrate eligibility based on HCl and chlorine emissions may avoid the need to install scrubbers to control certain air toxics emissions. However, these boilers or process heaters may be required to install fabric filters to reduce particle emissions for a separate particle standard for boilers.

  • Boilers or process heaters fueled by dried wood may qualify to comply with an alternative emissions limitation based on their emissions of manganese. Particulate matter controls may not be needed to comply with this alternative limitation, but these units may still be required to install other emissions controls.

  • Facilities that are eligible for compliance alternatives established by the final rule must assume federally enforceable emissions limitations. These limits ensure that their air toxics emissions do not exceed levels used to qualify for the compliance alternative.

  • EPA continues to believe that the alternative compliance options will maintain low levels of emissions while providing flexibility for plant managers to meet the final emission limits by altering their work practices in ways that will reduce emissions, or they may install emissions control devices such as fabric filters and scrubbers to chemically or physically remove air toxics from the boiler or process heater emissions streams.

  • EPA is still reviewing a petition, filed by the General Electric Corporation (GE) requesting reconsideration of the emission averaging provision in the final rule to address how this provision might apply in the context of affected boilers that vent to a common stack.

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  • The reconsideration notice is posted at: https://www3.epa.gov/ttn/oarpg/t3pfpr.html.

  • Today's reconsideration notice and other background information are also available either electronically in EDOCKET, EPA's electronic public docket and comment system, or in hardcopy at EPA's Air and Radiation Docket and Information Center, Environmental Protection Agency, Room B102, 1301 Constitution Avenue, NW, Washington, DC (Docket ID No. OAR-2002-0048 (Legacy Docket ID No. A-98-44)). The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is (202) 566-1744, and the telephone number for the Air and Radiation Docket and Information Center is (202) 566-1742.

  • HOW TO COMMENT. Comments should be identified by Docket ID No. OAR-2002-0058 (Legacy Docket ID No. A-96-47) and submitted by one of the following methods:
    • online through the Federal eRulemaking Portal ( http://www.regulations.gov );
    • by e-mail ( a-and-r-docket@epa.gov );
    • by fax to (202) 566-1741;
    • by mail (Air and Radiation Docket and Information Center, Environmental Protection Agency, Mailcode: 6102T, 1200 Pennsylvania Avenue, NW, Washington, DC 20460); or
    • by hand-delivery to (Air and Radiation Docket and Information Center, Environmental Protection Agency, Room B102, 1301 Constitution Avenue, NW, Washington, DC).

  • For more information about the reconsideration notice, contact Mr. Jim Eddinger at EPA's Office of Air Quality Planning and Standards at (919) 541-5426 or by e-mail at eddinger.jim@epa.gov.

  • EPA's Office of Air and Radiation (OAR) home page on the Internet contains a wide range of information on the air toxics program, as well as many other air pollution programs and issues. The OAR home page address is: https://www.epa.gov/oar.

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