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Final Amendments: Air Toxics Standards for Ethylene Production - Risk and Technology Review

On March 12, 2020, EPA finalized amendments to the 2002 Ethylene Production National Emission Standard for Hazardous Air Pollutants (NESHAP). EPA evaluated the risks remaining after fully implementing the NESHAP and determined that risks from the Ethylene Production source category are acceptable and that the standards provide an ample margin of safety to protect public health and the environment. In addition, the agency identified cost-effective developments in practices, processes or control technologies for heat exchange systems that would further reduce emissions of hazardous air pollutants.

EPA is also finalizing amendments for flares, pressure relief device releases, the decoking of ethylene cracking furnaces, and storage vessel degassing operations and clarifying that the standards are applicable during periods of startup, shutdown and malfunction. This proposal also includes electronic reporting of compliance reports and performance test results and reports. These amendments are being finalized to go into effect upon an affected source’s initial startup or within three years from promulgation, whichever is later.

For more information on the rule, visit the regulation page for Ethylene Production: National Emission Standards for Hazardous Air Pollutants (NESHAP).

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