The EPA, Residual Risk and Technology Review (RTR) & Ethylene Production Facilities (EMACT)

On October 9 and 23, 2019, the U.S. Environmental Protection Agency (EPA) published the proposed National Emission Standards for Hazardous Air Pollutants (NESHAP): Generic Maximum Achievable Control Technology Standards Residual Risk and Technology Review (RTR) for Ethylene Production Facilities (EMACT).

Under the Clean Air Act, EPA is required to perform a one-time risk review of the current rule eight years from the original date of promulgation. This risk review evaluates whether the HAP/volatile organic compound (VOC) reductions achieved also meet acceptable health risk levels or if the rule needs to be modified to further reduce regulated pollutants. Additionally, every eight years beginning from the date of promulgation, EPA must perform a technology review to evaluate if there have been developments in practices, processes, or control technologies that would be appropriate to incorporate into the standards.

The October EPA proposal satisfies both of the above review requirements and is known as an RTR. In developing the proposal, EPA drew upon the past review and promulgation of subject matters consistent with those found in the Benzene Waste Operation NESHAP (BWON), Miscellaneous Organic NESHAP (MON), Hazardous Organic NESHAP (HON), Petroleum Refinery Sector Rule (RSR), and New Source Performance Standards (NSPS) for Equipment Leaks Subpart VVa. For this reason, similar regulatory language is now being cited in the proposed EMACT rule.

Key impacts of the proposed ruling

  • Removal of the start-up, shutdown, and malfunction (SSM) exemption and no SSM plans required
  • Increased flare management equipment/practices, monitoring, recordkeeping, and reporting
  • Increased visible emissions monitoring
  • Removal of the in-situ sampling systems exemption
  • Increased monitoring, recordkeeping, and reporting for maintenance activities resulting from periodically discharged streams, equipment cleaning and purging, and isolating systems; general duty will apply
  • Removal of the ethylene cracking furnace decoking operations exemption
  • Expanded storage tanks’ capacity ranges for standard applicability
  • Change in leak detection and repair (LDAR) monitoring method along with decreased repair time and increased sampling
  • Required electronic reporting only and more data reporting for standard violations
  • Streamlined applicability for sources with overlapping rules, as well as clearer General Provisions

Impacted regulatory subparts

  • 40 CFR 63 Subpart SS (APCD)
  • 40 CFR 63 Subpart YY (GMACT)
  • 40 CFR 63 Subpart XX (Ethylene MFG: Heat Exchange/Waste)
  • 40 CFR 63 Subpart A (General Provisions)
  • 40 CFR 63 Subpart WW (Tanks)
  • 40 CFR 63 Subpart TT (Leaks L1)
  • 40 CFR 63 Subpart UU (Leaks L2)

Affected sources

  • Process vents
  • Storage vessels
  • Transfer operations
  • Equipment leaks
  • Waste
  • Heat exchange systems
  • Ethylene cracking furnaces and associated decoking operations

Prominent emitted HAPs

  • 1,3-butadiene
  • Benzene
  • Epichlorohydrin
  • Hexane
  • Manganese
  • Napthalene
  • Polycyclic organic matter (POM)
  • Toluene
  • Volatile organic compounds (VOCs)
  • Xylenes

Planning for future EMACT compliance

Trihydro has extensive experience with the referenced regulations in the EMACT RTR, such as the RSR and BWON, and can provide insights, applicability determinations, and sustainable compliance solutions once the proposed changes take effect.

Once the rule is promulgated, existing sources have three years to comply with the amendments, and new sources must comply upon start-up. Trihydro’s team of experts can help you position your facility for timely future compliance.

FieldVision™ integrated software for recordkeeping and reporting

The final ruling will require increased monitoring, recordkeeping, and types of reported data. Trihydro leveraged 35 years of regulatory experience and the latest technology to develop a new intuitive online dashboard and mobile app for streamlined data collection and management called FieldVision. FieldVision can be configured to your facility’s specific compliance needs to save valuable time in the field and office.
Calvin Niss
Calvin Niss
Senior Consultant, Laramie, WY

Cal has supervised and managed environmental projects in the petrochemical industry for over 30 years. His experience in the petrochemical industry includes numerous Clean Air Act compliance projects involving Benzene Waste Operations NESHAP (BWON), Consent Decree compliance, Hazardous Organic NESHAP (HON), leak detection and repair (LDAR), Maximum Achievable Control Technology (MACT), Miscellaneous Organic NESHAP (MON), and NSPS Subpart QQQ. He has provided expert testimony on both groundwater and air compliance issues, including testifying as an expert witness for the United States government.

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