Q495. Which takes precedence for determining the Subpart W applicability of a natural gas processing facility- the 25,000 MT CO2e threshold (under 98.2(a)(2)) or the 25 MMscf per day throughput (under 98.230(a)(3))?

A495. Please note that the amendments to the rule on May 14, 2024, eliminated the 25 MMscf per day throughput threshold beginning in Reporting Year (RY) 2025. For prior reporting years, both the 25,000 metric ton CO2e threshold (from 40 CFR 98.2(a)(2)) and the 25 MMscf per day annual average throughput (from 40 CFR 98.230(a)(3)) are considered when determining subpart W applicability for a non-fractionating natural gas processing facility.

If the throughput of a non-fractionating facility is greater than the 25 MMscf per day throughput threshold and the facility separates natural gas liquids (NGLs) or non-methane gases from produced natural gas as specified in the onshore natural gas processing industry segment definition in 40 CFR 98.230(a)(3), then the facility is in the onshore natural gas processing industry segment and emissions from all emissions sources listed in 40 CFR 98.232(d) (plus all emissions from stationary fuel combustion units and all other source categories listed in Tables A-3 and A-4 of subpart A) must be included in the applicability determination for the facility. If the throughput is less than 25 MMscf per day, then the facility does not meet the criteria in 40 CFR 98.230(a)(3) and is not a gas processing facility under subpart W. However, as discussed in FAQ484, for RY2016 through RY2024, such a site must be evaluated annually for possible inclusion in an onshore petroleum and natural gas gathering and boosting facility.

If the processing facility has less than 25,000 metric tons CO2e in combined emissions from stationary combustion, flaring, vented, and fugitive sources, then the site by itself is not subject to reporting under subpart W. However, as for facilities with throughput less than 25 MMscf per day, the owner or operator would need to determine if the site should be included in an onshore petroleum and natural gas gathering and boosting facility.

Beginning in RY 2025, the 25 MMscf per day throughput threshold is no longer used to define onshore natural gas processing in 40 CFR 98.230(a)(3). Therefore, for any processing facility that does not meet the definition of onshore natural gas processing in the amended 40 CFR 98.230(a)(3) in RY 2025, regardless of throughput, you must determine whether the processing operations should be reported under the Onshore Petroleum and Natural Gas Gathering and Boosting industry segment for RY 2025.