16 U.S.C. § 428n

Upon acquisition of the additional lands pursuant to authority contained in sections 428k to 428 o of this title, the Fort Donelson National Military Park shall be redesignated by the Secretary of the Interior as the Fort Donelson National Battlefield, notice thereof shall be published in the Federal Register, and any remaining balance of funds appropriated for purposes of the Fort Donelson National Military Park shall be available for the purposes of the Fort Donelson National Battlefield.