On August 13, 2020, U.S. Environmental Protection Agency (EPA) finalized two amendments - one policy and one technical - to New Source Performance Standards (NSPS) Subparts OOOO and OOOOa. The policy amendment primarily consists of two actions. The first removes the natural gas transmission and storage segment of the oil and gas industry from regulation under the rules, and the second removes the methane requirements in Subpart OOOOa.
EPA asserted a formal finding, that pollutants emitted from the natural gas transmission and storage segment contribute significantly to air pollution, was not completed during the original rulemaking and would need to be made before regulating sources in this segment. By removing methane from regulation, EPA is no longer required to issue emission guidelines for existing sources under Clean Air Act section 111(d). EPA notes that since the Volatile Organic Compounds (VOC) emission limits remain, methane reductions will not change as a result of this policy amendment. EPA also expects the natural gas industry will continue to reduce methane emissions through a combination of market incentives, state regulation, and/or participation in voluntary programs.
The technical amendments only affect NSPS OOOOa, and some of the more significant changes include:
- Adding an exemption from leak detection and repair (LDAR) requirements for low producing wells (and including a definition and determination procedure)
- Reducing frequency of leak inspections at compressor stations from quarterly to semiannually
- Allowing operators to comply with state LDAR programs in lieu of EPA's requirements
- Providing additional clarification on how to calculate potential emissions from storage vessels
- Revising certification requirements for closed vent systems to include professional engineers or in-house engineers
- Updating definitions and revising record keeping and reporting requirements to reduce burden and provide clarity
The policy amendments will become final on the date of publication in the Federal Register, and the technical amendments will become final 60 days after publication.