Q329. Is a blend of natural gas and biogas a unique fuel type that must be added?

A329. The reporting requirement depends on what information is known about the relative portions of each fuel. If the fuels to be blended are received separately and if the quantity of each fuel is measured before the fuels are mixed and combusted, then calculate and report the CO2 mass emissions separately for each fuel that is blended. If the fuel is received as a blend, or if the components are mixed on site, and the precise quantity of each fuel is not measured or known, then the use of the blended fuel type should be used. (See §98.33(e), §98.34(a)(3), and §98.34(b)(3)(v).)