The rule, covering 218 organic chemical and polymer manufacturing plants, imposes stringent emission limits on six chemicals without exemptions for startup, shutdown, and malfunction.

By Karl Karg, Phil Sandick, and Nate Gelfand-Toutant

On April 9, 2024, the US Environmental Protection Agency (EPA) issued a final rule amending the Clean Air Act New Source Performance Standards (NSPS) that apply to emissions from the Synthetic Organic Chemical Manufacturing Industry (SOCMI). The rule also finalizes amendments to the National Emission Standards for Hazardous Air Pollutants (NESHAP) that apply to the SOCMI (also called the Hazardous Organic NESHAP or HON) and to Group I and II Polymers and Resins Industries (P&R I and P&R II). Some of these amendments include updates to the maximum available treatment technology (MACT) standards, including those addressing heat exchange systems, storage vessels, and process vents, depending on the source category.

The rule will be effective 60 days after publication in the Federal Register but will likely be challenged.