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Ferromanganese and Silicomanganese Production: National Emission Standards for Hazardous Air Pollutants (NESHAP)

Rule Summary

The EPA published a final rule for the Ferroalloys Production source category included, among other things, the following:

  • Emissions limits for particulate matter (PM) from stacks for the electric arc furnaces (EAF), metal oxygen refining (MOR) processes, and crushing and screening operations to minimize PM emissions from these units;
  • Emission limits for: formaldehyde, hydrogen chloride, mercury, and PAH;
  • Requirements to capture process fugitive emissions using effective, enhanced local capture, and duct the captured emissions to control devices;
  • An average opacity limit of 8 percent during a full furnace cycle, and a maximum opacity limit of 20 percent for any two consecutive 6-minute periods, to ensure effective capture and control of process fugitive emissions;
  • A requirement to conduct opacity observations using the DCOT at least once per week for a full furnace cycle for each operating furnace and each MOR operation for at least 26 weeks. After 26 weeks, if all tests are compliant, facilities can decrease to monthly opacity observations;
  • A requirement to use BLDS to monitor PM emissions from all furnace baghouses; and
  • A requirement to conduct periodic performance testing to demonstrate compliance with the stack emission limits for the various HAP, including a requirement to conduct PAH performance testing every 3 months for furnaces producing FeMn for the first year with the opportunity to reduce to annual testing after the first year.

Rule History

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.1/18/2017 - Reconsideration; final rule.

07/12/2016 - Reconsideration; proposed rule.

06/30/2015 - Final rule.

12/05/2014 - Supplemental notice of proposed rulemaking; extension of public comment period.

11/14/2014 - Supplemental notice of proposed rulemaking; extension of public comment period.

10/15/2014 - Supplemental notice of proposed rulemaking; correction.

10/06/2014 - Supplemental notice of proposed rulemaking.

12/29/2011 - Proposed rule; extension of public comment period.

11/23/2011 - Proposed rule.

12/23/2008 - Final rule.

03/22/2001 - Proposed rule; amendments.

03/22/2001 - Direct final rule; amendments.

05/20/1999 - Final rule.

02/12/1999 - Supplement to proposed rules; Notice of public hearing.

10/13/1998 - Proposed rule; extension of public comment period.

08/04/1998 - Proposed rules; notice of public hearing.

Additional Resources

Fact Sheet - Ferroalloys Reconsideration Final Rule December 2016

Fact Sheet - Ferroalloys Reconsideration Proposal June 2016 (published 7.12.16)

Economic Impact Analysis

Residual Risk Assessment for the Ferroalloys Source Category in Support of the September Supplemental Proposal 

Technical Document for Promulgation of Standards: Comment and Response Summary

Fact Sheet - Final Amendments to the Air Toxics Standards for Ferroalloys Production

Fact Sheet - Final Air Toxics Rule for Ferromanganese and Silicomanganese Production

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