the Government share of the cost of the project. (2) Grants financed from general fund A grant or contract that is approved by the Secretary and financed with amounts appropriated in advance from the general fund of the Treasury pursuant to this section is a contractual obligation of the Government to pay the Government share of the cost of the project only to the extent that amounts are appropriated for such purpose by an Act of Congress. (f) Availability of amounts Amounts made available by or appropriated under this section shall remain available until expended. . (b) Conforming amendments (1) Section 5311 of title 49, United States Code, is amended by striking 5338(a)(2)(F) and inserting 5338(a)(2)(E) . (2) Section 5312(i)(1) of title 49, United States Code, is amended by striking 5338(a)(2)(G)(ii) and inserting 5338(a)(2)(F)(iii) . (3) Section 5333(b) of title 49, United States Code, is amended by striking 5328, 5337, and 5338(b) each place it appears and inserting and 5337 . (4) Section 5336 of title 49, United States Code, is amended— (A) in subsection (d)(1) by striking 5338(a)(2)(C) and inserting 5338(a)(2)(B)