70 ILCS 1905/15
Whenever the Board of Commissioners determines that a particular area is a Railroad Terminal Area, as herein defined, and should be acquired pursuant to the provisions of this Act, such determination together with an accurate description of the area included in such determination and the date on which the determination was made shall be set forth in the records of the Authority. Any such determination may include additional property situated outside the Railroad Terminal Area which the Board of Commissioners determines is necessary to be acquired in connection with the construction of a railroad terminal and facilities appurtenant thereto. The area may be enlarged, from time to time, as the Board of Commissioners may determine. Each such determination shall be evidenced by a resolution adopted by at least four (4) members of the Board of Commissioners and a certified copy of such resolution shall be delivered to the city council of the city in which the Authority is organized. No such determination shall be of any force or effect until such time as it has been approved by the city council of that city, and after such approval a certified copy of such approval and resolution of the Authority shall be filed in the office of the recorder.
70 ILCS 1905/15