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Mercury Cell ChlorAlkali Plants: National Emissions Standards for Hazardous Air Pollutants (NESHAP)

Mercury Cell ChlorAlkali Plants: National Emissions Standards for Hazardous Air Pollutants (NESHAP)
Basic Information
Legal Authorities
  • 42 U.S.C. §7401
Federal Register Citations
  • 76 FR 13852
  • 73 FR 33257
  • 68 FR 70904
  • 67 FR 54400
  • 67 FR 44713
  • 67 FR 44672
Code of Federal Regulations Citations
  • 40 CFR Part 63 Subpart IIIII
Docket Numbers
  • EPA-HQ-OAR-2020-0560
  • EPA-HQ-OAR-2002-0017

On this page:

  • Rule Summary
  • Rule History
  • Additional Resources

Rule Summary

This action promulgates national emission standards for hazardous air pollutants (NESHAP), specifically mercury emissions, from mercury cell chlor-alkali plants. The final rule limits mercury air emissions from these plants. The final rule implements

Comment Period Extension

The public comment period for the proposed RTR has been extended until March 24, 2021.

section 112(d) of the Clean Air Act (CAA) which requires all categories and subcategories of major sources and area sources listed under section 112(c) to meet hazardous air pollutant emission standards reflecting the application of the maximum achievable control technology (MACT).

Rule History

05/06/2022 - Final rule (May 2022)

02/12/2021 - Pre-publication proposed rule; extension of public comment period (pdf) (237 KB)

01/08/2021 - Proposed rule (January 2021) | Proposed rule edits

03/14/2011 - Supplemental proposed rule (pdf) (397 KB)

06/11/2008 - Proposed rule (June 2008) (pdf) (300 KB)

12/19/2003 - Final rule (December 2003) (pdf) (305 KB)

08/22/2002 - Proposed rule; extension of public comment period (pdf) (130 KB)

07/03/2002 - Proposed rule (July 2002) (pdf) (300 KB) & Proposed decision not to regulate (pdf) (151 KB)

Additional Resources

Fact Sheet: Final Amendments to Air Toxics Standards for Mercury Cell Chlor Alkali Plants (pdf) (176.67 KB, 04/29/2022)

Fact Sheet: Proposed Amendments to Air Toxics Standards for Mercury Cell Chlor-Alkali Plants

Public Comment Review Tool for Mercury Cell ChlorAlkali Plants (zip) . To use this tool, please download the file to your computer and unzip, then follow the instructions in the included PDF file.

Fact sheets

View the supporting documents in the docket folder to find additional related documents to the rules.

Stationary Sources of Air Pollution

  • Regulations
    • Industry Sector Groups
    • National Emission Standards for Hazardous Air Pollutants (NESHAP)
      • Area Source Standards
      • Risk and Technology Review Status
    • New Source Performance Standards
    • Good Neighbor Plan for the 2015 Ozone National Ambient Air Quality Standards
  • Small Business Assistance Program
Contact Us About Stationary Sources of Air Pollution
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Last updated on March 27, 2025
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