20 ILCS 825/1
The Department of Natural Resources, with the approval and consent of the Governor, is authorized to enter into contracts with the Federal Government, or the proper department or agency thereof authorized by Act of Congress, for the conveyance of lands of the State of Illinois in this State under the jurisdiction of the Department to the Federal Government, and to receive in exchange therefor, in the name of the State of Illinois, title to lands of the Federal Government in this State, for forest purposes and for the development, management and maintenance of a state-wide system of recreational and water storage lakes for the preservation of wildlife, hunting, fishing and recreation, reforestation and wildlife planting, when, in the judgment of the Department, such exchange is advantageous to the State for the orderly development and management of such lands for the purposes herein enumerated. The Department of Natural Resources is hereby authorized to purchase and receive title to lands within this State to effectuate and carry out the purposes of this Act and the Fish and Aquatic Life Code and Wildlife Code of this State; provided that such exchange of lands shall not be contrary to the terms of any contract or agreement entered into for those purposes.
20 ILCS 825/1