620 ILCS 5/34
The Department, subject to the provisions of Section 41 of this Act, may render financial assistance in the planning, construction, reconstruction, extension, development, and improvement of air navigation facilities including acquisition of land, rights in land, easements including avigation easements necessary for clear zones or clear areas, costs of obstruction removal and airport approach aids owned, controlled, or operated, or to be owned, controlled, or operated by municipalities, other political subdivisions of this State, or privately owned commercially operated airports in Illinois, out of appropriations made by the General Assembly for any such purpose. The Department shall not render such financial assistance in connection with the planning, construction, reconstruction, extension, development or improvement of hangars or other airport buildings, or in connection with the subsequent operation or maintenance of such air navigation facilities unless such facilities are for public use, publicly owned, and of public benefit. As used in this Section, "of public benefit" includes aircraft hangars, fixed-based operator buildings, and aircraft maintenance buildings at nonprimary airports included within the State Airport Plan. The municipality, other political subdivision, or privately owned commercially operated airports in Illinois, to which such financial assistance is being extended by the Department, before such financial assistance is given, shall satisfy the Department that (a) such air navigation facility will be owned or effectively controlled, operated, repaired and maintained adequately during its full useful life, for the benefit of the public, and (b) in connection with the operation of such air navigation facility, during its full useful life, the public will not be deprived of its rightful, fair, equal and uniform use thereof. The owners and operators of an airport receiving financial assistance under this Act must adequately control, operate, repair, and maintain the airport during its full useful life for the benefit of the public. The owners and operators of an airport receiving financial assistance must ensure that the public will not be deprived of its rightful, fair, equal, and uniform use of the airport during its full useful life. For the purposes of this paragraph, the full useful life of an airport is not less than 20 years after the financial assistance is received by the owners and operators of the airport. Nothing in this Section, however, imposes any obligation that is inconsistent with any judgment, order, injunction, or decree of any court that was rendered before the effective date of this amendatory Act of the 92nd General Assembly.
Any commercial airport, in order to qualify under the provisions of this Section must be included in the State Airport Plan as prepared or revised from time to time by the Illinois Department of Transportation. In the case of commercial public use airports which are not publicly owned airports, no such development or planning may be proposed except in connection with reliever airports included in the current National Airport System Plan.
Improvements to privately owned commercial airports qualifying under this Section shall be contracted for and constructed or developed under the supervision or direction of the Department or such other Department, agency, officer or employee of this State as the Department may designate.
If a privately owned commercially operated airport receives assistance under this Section and ceases operations before the predetermined life of the improvements made with such assistance, the State shall be reimbursed for the unused portion of such predetermined life and such claim shall be a lien on the airport property.
620 ILCS 5/34