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74 FR 56374, Oct. 30, 2009, unless otherwise noted.
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At 90 FR 21227, May 19, 2025, as required by the Congressional Review Act and Public Law 119-2, the Environmental Protection Agency removed the amendments to §§ 98.3 and 98.4 made effective on Jan. 17, 2025, at 89 FR 91163, Nov. 18, 2024. As of May 19, 2025, §§ 98.3 and 98.4 reverted to the Jan. 16, 2025 version.
| Fuel | Unit | Default CO2 emission factor (MT CO2/Unit) 1 |
|---|---|---|
| Natural Gas | Mscf | 0.0544 |
| Propane | Barrel | 0.241 |
| Normal butane | Barrel | 0.281 |
| Ethane | Barrel | 0.170 |
| Isobutane | Barrel | 0.270 |
| Pentanes plus | Barrel | 0.324 |
| 1 Conditions for emission value presented in MT CO2/bbl are 60 °F and saturation pressure. | ||
[78 FR 71977, Nov. 29, 2013, as amended at 79 FR 3508, Jan. 22, 2014; 81 FR 89270, Dec. 9, 2016]