Regulatory Alert - Aug 2020 - Proposed Changes to the Major Source Boiler MACT

Aegis extends this brief regulatory alert:

On July 22nd, the EPA announced proposed changes to the National Emission Standards for Hazardous Air Pollutants (NESHAP) for major source industrial, commercial, and institutional boilers and process heaters. The rulemaking addresses several Court remands of the 2013 final rule.  The major issue centered on EPA’s Maximum Achievable Control Technology (MACT) floor analysis used to set standards for the various boiler/process heater categories. In response, EPA is proposing changes to 34 of the 90 MACT emissions standards.  Boiler categories with more restrictive limits will include the following:  new solid (HCl), biomass (CO, PM, TSM), and liquid (HCl, PM, TSM); and existing solid (HCl, Hg), coal (PM, CO), biomass (PM, CO, TSM), and liquid (Hg, PM). Less restrictive limitations are proposed for existing and new biomass and gas boilers. The rule was published in the Federal Register on July 8, 2020.  Facilities will have up to three years from this date to comply with the new limitations. The EPA will be accepting comments on the changes for 60 days from July 8.  The proposed changes can be found at: EPA MACT Amendment News.  For more information, please contact Sandra Morse here at