112 STAT. 348 PUBLIC LAW 105-178^JUNE 9, 1998 section 5336 for a fiscal year shall be made available for transit enhancement activities in accordance with section 5302(a)(15). "(2) PERIOD OF AVAILABILITY.— Funds apportioned under paragraph (1) shall be available for obligation for 3 years following the fiscal year in which the funds are apportioned. Funds that are not obligated at the end of such period shall be reapportioned under the urbanized area formula program of section 5336. "(3) REPORT. —^A recipient of funds apportioned under paragraph (1) shall submit, as part of the recipient's annual certification to the Secretary, a report listing the projects carried out during the fiscal year with those funds.", (g) CONFORMING AMENDMENTS.— Section 5307(n)(2) is amended by inserting "5319," after "5318,". SEC. 3008. CLEAN FUELS FORMULA GRANT PROGRAM. (a) IN GENERAL. —Section 5308 is amended to read as follows: ^§ 5308. Clean fuels formula grant program "(a) DEFINITIONS.—In this section— "(1) the term 'clean fuel vehicle' means a vehicle that— "(A) is powered by— "(i) compressed natural gas; "(ii) liquefied natural gas; " (iii) biodiesel fuels; "(iv) batteries; "(v) alcohol-based fuels; "(vi) hybrid electric; "(vii) fuel cell; "(viii) clean diesel, to the extent allowed under this section; or "(ix) other low or zero emissions technology; and "(B) the Administrator of the Environmental Protection Agency has certified sufficiently reduces harmful emissions; "(2) the term 'designated recipient' has the same meaning as in section 5307(a)(2); and "(3) the term 'eligible project'— "(A) means a project for— "(i) purchasing or leasing clean fuel buses, including buses that employ a lightweight composite primary structure; "(ii) constructing or leasing clean fuel buses or electrical recharging facilities and related equipment; "(iii) improving existing mass transportation facilities to accommodate clean fiiel buses; "(iv) repowering pre-1993 engines with clean fuel technology that meets the current urban bus emission standards; or "(v) retrofitting or rebuilding pre-1993 engines if before half life to rebuild; and "(B) in the discretion of the Secretary, may include projects relating to clean fuel, biodiesel, hybrid electric, or zero emissions technology vehicles that exhibit equivalent or superior emissions reductions to existing clean fuel or hybrid electric technologies.