it enters the United States. (e) Point of Taxation The point of taxation shall be— (1) for products manufactured in the United States, the manufacturing facility, (2) for products imported into the United States, the point at which it first enters the United States, and (3) for domestically produced biomass fuel by a facility that emits from combusted biomass fuel more than 25,000 metric tons of carbon dioxide equivalent greenhouse gases in a year, the facility that combusts the biomass fuel. 9904. Calculation of taxable emissions (a) How To calculate taxable emissions In consultation with the Department of Energy, the Administrator shall establish by rule (and may, from time to time, revise) the method by which taxable emissions under this part shall be calculated. (b) Categories and subcategories considered For purposes of calculating emissions taxable under— (1) section 9901, the Administrator shall determine by rule the amount of carbon dioxide equivalent that would be emitted if each fossil fuel were combusted, and the Administrator may establish by rule such subcategories of each fuel and the means by which it is combusted as the Administrator deems appropriate, (2) section 9902, the Administrator may determine by rule such subcategories of any industrial process category listed in subsection 9902(b) as the Administrator deems appropriate, and (3) section 9903, for fuel ethanol, biodiesel, and solid biomass fuels the Administrator shall determine by rule the amount of carbon dioxide equivalent that would be emitted based on the lifecycle greenhouse gas emissions of the product, and the Administrator may determine by rule such subcategories of manufactured products listed in subsection 9903(b) as the Administrator deems appropriate. (c) Methods Where greenhouse gas emissions subject to taxation under any section of this part are combined with greenhouse gas emissions subject to taxation under any other section of this part, the Administrator shall ensure, to the greatest degree possible, that the methods