((a)) ** .—** Nothing in this title, or in any other provision of law, shall be construed to prevent a person whose real property is being acquired in connection with a project under this title, after he has been fully informed of his right to receive just compensation for the acquisition of his property, from making a gift or donation of such property, or any part thereof, or of any of the compensation paid therefor, to a Federal agency, a State or a State agency, or a political subdivision of a State, as said person shall determine.

((b))

((1)) ** .—** Notwithstanding any other provision of this title, the State share of the cost of a project with respect to which Federal assistance is provided from the Highway Trust Fund (other than the Mass Transit Account) may be credited in an amount equal to the fair market value of any land that—

((A)) is lawfully obtained by the State or a unit of local government in the State;

((B)) is incorporated into the project;

((C)) is not land described in section 138; and

((D)) the Secretary determines will not influence the environmental assessment of the project, including—

((i)) the decision as to the need to construct the project;

((ii)) the consideration of alternatives; and

((iii)) the selection of a specific location.

((2)) ** .—** The fair market value of land incorporated into a project and credited under paragraph (1) shall be established in the manner determined by the Secretary, except that—

((A)) the fair market value shall not include any increase or decrease in the value of donated property caused by the project; and

((B)) the fair market value of donated land shall be established as of the earlier of—

((i)) the date on which the donation becomes effective; or

((ii)) the date on which equitable title to the land vests in the State.

((3)) ** .—** This subsection shall not apply to donations made by an agency of the Federal Government.

((4)) ** .—** The credit received by a State pursuant to this subsection may not exceed the State’s matching share for the project.

((c)) ** .—** Nothing in this title or any other law shall prevent a person from offering to donate funds, materials, or services, or a local government from offering to donate funds, materials, or services performed by local government employees, in connection with a project eligible for assistance under this title. In the case of such a project with respect to which the Federal Government and the State share in paying the cost, any donated funds, or the fair market value of any donated materials or services, that are accepted and incorporated into the project by the State transportation department shall be credited against the State share.

((d)) ** .—** A gift or donation in accordance with subsection (a) may be made at any time during the development of a project. Any document executed as part of such donation prior to the approval of an environmental document prepared pursuant to the National Environmental Policy Act of 1969 ( et seq.) shall clearly indicate that—

((1)) all alternatives to a proposed alignment will be studied and considered pursuant to such Act;

((2)) acquisition of property under this section shall not influence the environmental assessment of a project including the decision relative to the need to construct the project or the selection of a specific location; and

((3)) any property acquired by gift or donation shall be revested in the grantor or successors in interest if such property is not required for the alignment chosen after public hearings, if required, and completion of the environmental document.