GRANT AGREEMENTS.

SEC. 110. GRANT AGREEMENTS. (a) Maximum Obligation of the United States.— Section 512(b) is amended to read as follows: “(b) Maximum Obligation of the United States.— “(1) General rule.— Subject to paragraphs (2) and (3) of this subsection, when an offer is accepted in writing by a sponsor, the amount stated in the offer as the maximum obligation of the United States may not be increased. “(2) Exceptions for fiscal years 1987 and before.— The maximum obligation of the United States under this subsection with respect to a project receiving assistance under a grant approved under this title on or before September 30, 1987, may be increased— “(A) by not more than 10 percent in the case of a project for airport development (other than a project for land acquisition); and “(B) by an amount not to exceed 50 percent of the total increase in allowable project costs attributable to an acquisition of land or interests in land, based upon current credible appraisals. Any increase under this section may be paid only from funds recovered by the United States from other grants made under this title. “(3) Exceptions for fiscal years 1988 and thereafter.— The maximum obligation of the United States under this subsection with respect to a project receiving assistance under a grant approved under this title or the Aviation Safety and Noise Abatement Act of 1979 after September 30, 1987, may be increased by not more than 15 percent in the case of a project for airport development.”. (b) Workscope.— Section 512 is amended by adding at the end thereof the following new subsection: “(d) Workscope.— The Secretary may amend, with the consent of the grant recipient, a grant agreement entered into under this title to change the workscope of a project funded under such grant if such amendment does not result in any increase in the maximum obligation of the United States authorized under subsection (b) of this section.”. (c) Conforming Amendment.— Section 512(c) is amended by inserting “Maximum Obligation for Grants Under the Airport and Airway Development of 1970.—” before “Notwithstanding”.