; and (2) transfer portions of those funds to the Administrators of the Federal Highway Administration, the Federal Transit Administration, the Federal Railroad Administration, and the Maritime Administration. (o) Period for obligation of funds (1) In general Funds made available for a fiscal year to carry out the program shall remain available to the Secretary for obligation under the program for a period of 3 years after the last day of the fiscal year for which the funds are authorized. (2) Transfer of unobligated funds Any amounts made available to carry out the program that remain unobligated at the end of the 3-year period referred to in paragraph (1) shall be transferred to the Highway Trust Fund. (p) Funding There shall be available, without further appropriation, from the National Infrastructure Investment Trust Fund for expenditure by the Secretary to carry out the program $3,000,000,000 for each fiscal year. 3. Fixed guideway capital investment grants (a) Funding There shall be available from the Fixed Guideway Capital Investment Trust Fund, without further appropriation, for expenditure by the Secretary of Transportation to carry out section 5309 of title 49, United States Code, $9,000,000,000 for each fiscal year. (b) Administrative expenses Of the amounts made available for a fiscal year under subsection (a) to carry out section 5309 of title 49, United States Code, the Secretary may retain not more than 1 percent of the total funds made available to carry out such section to administer the award and oversee grants made under the program. (c) Period for obligation of funds (1) In general Funds made available for a fiscal year under subsection (a) to carry out section 5309 of title 49, United States Code, shall remain available to the Secretary for obligation under that section for a period of 4 years after the last day of the fiscal year for which the funds are authorized. (2) Transfer of unobligated funds Any amounts made available under subsection (a) to carry out section 5309 of title 49, United