On April 12, 2019, the U.S. Environmental Protection Agency (EPA) published proposed amendments to the National Emissions Standard for Hazardous Air Pollutants (NESHAP) for Stationary Combustion Turbines (Code of Federal Regulations [CFR], Title 40, Part 63, Subpart YYYY) in the Federal Register.
The proposed amendments address periods of startup, shutdown, and malfunction (SSM) electronic reporting and lift the stay of effectiveness of the standards for lean premix and diffusion flame gas-fired turbines that has been in effect since 2004. 40 CFR 63 Subpart YYYY only applies to combustion turbines located at major sources of hazardous air pollutants (HAPs).
The proposed amendments address the following:
- EPA is proposing to lift the stay of effectiveness of the standards for lean premix and diffusion flame gas-fired turbines that has been in effect since 2004. The proposed amendments state, “Turbines that are subject to the stay would be required to comply with all applicable regulatory requirements of 40 CFR part 63, subpart YYYY, immediately upon a final action to remove the stay. Required initial performance tests must be conducted within 180 calendar days after the effective date of the final action to remove the stay.”
[Note: The only current numerical emissions limit during normal operation is for formaldehyde and is 91 parts per billion volume dry (ppbvd) at 15-percent oxygen. Compliance must be demonstrated by conducting an initial and annual performance tests.]
- EPA is proposing to eliminate the SSM exemption and is proposing an operational standard during periods of startup in lieu of a numerical emissions limit. The proposed operational standard will require owners/operators to minimize time spent at idle and startup time not to exceed 1 hour for simple-cycle operation and 3 hours for combined-cycle operation. EPA is not proposing any additional standards during periods of shutdown or malfunction.
- EPA is proposing amending the General Provisions table to: (1) eliminate the requirement to develop an SSM plan, and (2) revise some associated recordkeeping and reporting requirements during periods of SSM.
- EPA is proposing amendments to require electronic reporting of performance test results and semiannual compliance reports through EPA’s Central Data Exchange (CDX) using the Compliance and Emissions Data Reporting Interface (CEDRI).
Comments to these proposed amendments can be submitted to EPA and must be received on or before May 28, 2019.