; or (B) adopt the methodology described in paragraph (1). (3) Establishment of fuel pathways For any fuel pathway to which the Administrator assigns a D code pursuant to a petition described in section 80.1416 of title 40, Code of Federal Regulations (or successor regulations), that is approved by the Administrator after the date of enactment of this Act, the Administrator shall, not later than 90 days after the date on which the Administrator assigns that code, adopt the methodology described in paragraph (1) for purposes of modeling lifecycle analyses with respect to greenhouse gas emissions that result from that fuel pathway. (c) Report If the Administrator fails to carry out subsection (b)(2) before the applicable deadline described in subsection (a), the Administrator shall submit to the Committees on Agriculture, Nutrition, and Forestry, Energy and Natural Resources, and Environment and Public Works of the Senate and the Committees on Agriculture, Energy and Commerce, and Science, Space, and Technology of the House of Representatives a report describing the reasons for the failure to carry out subsection (b)(2), which may include a determination by the Administrator that the methodology adopted or updated in a previous update under subsection (a) remains the most current methodology based on available data, research, and technology.