On Nov. 10, 2025, EPA proposed new hazardous air pollution regulations for Hazardous Waste Combustors (HWC), establishing emission limits and work practice standards for hydrogen fluoride and hydrogen cyanide. EPA anticipated that its new rule would not affect air quality standards since all affected HWCs already met these limits. Affected operations include hazardous waste incinerators, cement kilns, hydrochloric acid production furnaces and various types of boilers.
The proposal followed a 2022 lawsuit from environmental justice groups, which accused EPA of unlawfully delaying review of these standards. As a result of the suit, a federal district court ordered EPA to establish hazardous air pollutant standards for HWCs by Dec. 31, 2025. EPA accepted public comments through Dec. 26, 2025.
On June 3, 2026, EPA finalized its rule, with only minor deviations from its proposal.