Q543. For acid gas removal vents using Calculation Method 3 (40 CFR 98.233(d)(3), are we allowed to make the conservative assumption that volume fraction of CO2 content in natural gas out of the AGR unit is zero?

Q543. For acid gas removal vents using Calculation Method 3 (40 CFR 98.233(d)(3), are we allowed to make the conservative assumption that volume fraction of CO₂ content in natural gas out of the AGR unit is zero?

A543. No.  40 CFR 98.233(d)(8) does not instruct reporters using Calculation Method 3 to assume a volumetric fraction of zero for Vol₀.  Reporters must use one of the methods specified in 40 CFR 98.233(d)(8) to determine the CO₂ content of the natural gas exiting the AGR unit (Vol₀) for Calculation Method 3.