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Kraft, Soda, Sulfite, and Stand-Alone Semichemical Pulp Mills (MACT II): National Emission Standards for Hazardous Air Pollutants (NESHAP) for Chemical Recovery Combustion Sources

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Rule Summary

The chemical recovery process at pulp mills involves the recovery of chemicals in the spent cooking liquor, reconstitution of those chemicals, and the generation of energy from the incineration of the organic residuals. This subpart regulates the emissions from the pulp mill combustion sources, which are recovery furnaces, smelt dissolving tanks, and lime kilns. 

These standards do not address emissions from mills that chemically pulp wood using kraft, semi-chemical, sulfite, or soda processes that are referred to as MACT I mills. Mills that mechanically pulp wood, or that pulp secondary fiber or non-wood fibers, or that produce paper or paperboard from purchased pulp are referred to as MACT III mills, and these two MACTs are regulated under a seperate NESHAP.

The National Emissions Standards for Hazardous Air Pollutants (NESHAP) for the pulp mill combustion sources was originally proposed in 1998 and promulgated in 2001. In these actions, the EPA identified Hazardous Air Pollutants (HAP) metals as the HAP emitted in the largest quantity and regulated them through a particulate matter surrogate. Gaseous organic HAP were also regulated for new sources.

See the regulations in the section below for more details.

Subpart MM RTR Final Rule Supporting Documentation

Technical supporting documents for the final rule

Subpart MM RTR

Subpart MM RTR Supporting Documentation

Rule History

10/31/2019 - Proposed Amendments

10/11/2017 - Final Amendments: Residual Risk and Technology Review

12/30/2016 - Proposed Amendments; Risk and Technology Review

05/06/2004 - Final Rule; technical corrections

07/18/2003 - Final Rule; amendments

05/08/2003 - Correcting administrative amendments; change in effective date

02/18/2003 - Proposed Rule & Direct Final Rule

08/06/2001 - Federal Register Correction

07/19/2001 - Final Rule; technical corrections

01/12/2001 - Final Rule

04/15/1998 - Proposed Rule

Additional Resources

Fact Sheet:  Proposed Amendments to Air Toxics Standards for the Chemical Recovery Combustion Sources and the Kraft Pulp Mill New Source Performance Standards

Redline of NSPS Subpart BBa and MM

Fact Sheet:  Final Amendments to Air Toxics Standards for the Pulp and Paper Chemical Recovery Combustion Sources

Fact Sheet:  December 2016 Proposed Amendments; Risk and Technology Review

Chemcial Recovery Combustion Sources at U.S. Sulfite Pulp Mills

Technical Support Document: Chemical Recovery Combustion Sources at Kraft and Soda Pulp Mills

WATER9 is a Windows based computer program for estimating air emissions of individual waste constituents in wastewater/waste. Further information or a copy of the WATER 9 can be obtained from EPA. You can also contact the Air Emissions Model Hotline at (919) 541-5610 for support or more information about this model.

Pulp and paper manufacturing is subject to the Greenhouse Gas Reporting Program. Information regarding available and emerging technologies for reducing greenhouse gas emissions from pulp and paper manufacturing can be found here.

Related Rules

MACT I & III Pulp and Paper regulations

Kraft Pulp Mills: New Source Performance Standards (NSPS)

Pulp, Paper, and Paper Board Point Source Category Effluent Guidelines and Standards


Pulp and Paper Chemical Recovery Combustion Sources National Emission Standards for Hazardous Air Pollutants (NESHAP) 40 CFR Part 63 Subpart MM: Inspector Checklist

Applicability Determination Index (ADI).  The ADI is maintained by EPA's Office of Enforcement and Compliance Assurance (OECA) and provides a data base of memoranda dealing with applicability issues.  The database is searchable by Subpart.