On November 9, 2020, the U.S. Environmental Protection Agency (EPA) published proposed amendments to the 2012 National Emission Standards for Hazardous Air Pollutants (NESHAP) for Polyvinyl Chloride and Copolymers Production (PVC MACT). The proposed amendments, which are the result of industry and environmental group requests for reconsideration of the rule, propose to tighten certain maximum achievable control technology (MACT) limits, provide additional clarification about certain aspects of the rule, and eliminate waivers for excess emissions during a malfunction.
The revised PVC MACT includes a number of proposals. First, the amendment revises the definitions of and emission limits for certain process vent subcategories. The revised rule also clarifies that if a PVC production unit process vent merges with a non-PVC vent stream, and the two streams are vented through the same control device, both the PVC MACT and the MACT applicable to the other vent stream apply. Second, the proposal revises the process wastewater vinyl chloride emission limits and removes the total non-vinyl chloride organic HAP emission limit by establishing vinyl chloride as a surrogate. Third, EPA proposes clarifications to the stripped resin, storage vessel, equipment leak and closed vent system standards. Finally, EPA is removing the affirmative defense to civil penalties for system malfunctions that occur despite diligent efforts to prevent such events. EPA estimates the amendments will result in HAP emission reductions of 34 tons per year.
The 60-day comment period on the proposed rule ends on January 8, 2021.