16 U.S. Code § 430h–11 - Acquisition of property
(a) Pemberton’s Headquarters
The Secretary of the Interior is authorized to acquire the properties described in section 430h–10 of this title and subsection (b) of this section by purchase, donation, or exchange, except that each property may only be acquired with the consent of the owner thereof.
The Secretary is also authorized to acquire not more than one acre of land, or interest therein, adjacent to or near Pemberton’s Headquarters for the purpose of providing parking and other facilities related to the operation of Pemberton’s Headquarters. Upon the acquisition of the property referenced in this subsection, the Secretary shall add the property to Vicksburg National Military Park and shall modify the boundaries of the park to reflect its inclusion.