Q516. What are the equipment leak requirements for liquefied natural gas facility equipment that is in gas service? Is it only required to be reported if it is found to be leaking as defined in the rule?

A516. LNG storage facilities must perform equipment leak surveys of all components (e.g., from valves, pump seals, connectors, and other equipment leak components) in LNG service. LNG storage facilities are also required to survey equipment leak components in gas service, including those associated with the vapor recovery compressor, if the facility is subject to the well site or compressor station fugitive emissions standards in §60.5397a of this chapter, the fugitive emissions standards for well sites, centralized production facilities, and compressor stations in § 60.5397b or § 60.5398b of this chapter, or an applicable approved state plan or applicable Federal plan in part 62 of this chapter or if the facility voluntarily elects to do so. Otherwise, equipment leak components in gas service are reported following the population count method in 40 CFR 98.233(r)(4). For equipment leaks following the leaker method in 40 CFR 98.233(q), facilities must report the number of components found leaking (including reporting a 0 if the component was not found leaking), the annual average operating time the component was assumed to be leaking, and the GHG emissions for each component type. For equipment leaks following the population count method in 40 CFR 98.233(r), facilities must report the count of vapor recovery compressors present at the facility, the annual average operating time for the compressor(s), and the GHG emissions for the compressor(s).

It should be noted that at an LNG facility, a compressor that recovers vapor, but is designed so that it does not have reportable emissions of methane-containing gas, such as a flooded screw compressor, or one with seals purged with pressurized nitrogen, will not be reported, in accordance with the rule and the EPA’s response in Response to Public Comments, EPA-HQ-OAR-2009-0923-1026-7 (see pages. 45-46 in https://www.epa.gov/sites/production/files/2015-05/documents/subpart-w_rtc_part1.pdf).  Vapor recovery compressors use a population emission factor, hence there is no leak detection required.