; (3) no changes or alterations may be made to any properties covered by an agreement entered into under subsection (a) or (b) unless the Secretary and the other party to the agreement agree to the changes or alterations; and (4) any conversion, use, or disposal of a project for purposes contrary to the purposes of this Act, as determined by the Secretary, shall entitle the United States to reimbursement in an amount equal to the greater of— (A) the amounts made available to the project by the United States; and (B) the portion of the increased value of the project attributable to the amounts made available under this subsection, as determined at the time of the conversion or disposal. 9. Chesapeake gateways (a) In general The Secretary (acting through the Superintendent of the Chesapeake Bay Office of the National Park Service) shall administer Chesapeake Gateways in coordination with the Recreation Area. (b) Permanent authorization Section 502(c) of the Chesapeake Bay Initiative Act of 1998 ( 54 U.S.C. 320101 note; Public Law 105–312 ) is amended by striking to carry out this section $3,000,000 and all that follows through the period at the end and inserting to carry out activities authorized under this section $6,000,000 for each fiscal year. . (c) Effect Nothing in this section or an amendment made by this section modifies the eligibility criteria developed under section 502(b)(2) of the Chesapeake Bay Initiative Act of 1998 ( 54 U.S.C. 320101 note; Public Law 105–312 ). 10. Management plan (a) In general Not later than 3 years after the date on which funds are first made available for the preparation of a management plan for the Recreation Area, the Secretary, in consultation with the Chesapeake Executive Council (as defined in section 117(a) of the Federal Water Pollution Control Act ( 33 U.S.C. 1267(a) )) and the Advisory Commission, shall prepare a management plan for the Recreation Area, in accordance with— (1) section 7(e)(2)