620 ILCS 5/49
The Department is empowered to order the discontinuance or limitation, temporarily or permanently, of the operation of any airport or restricted landing area when it shall determine, after a hearing, that such airport or restricted landing area is not safe or is not being maintained or operated safely.
(from Ch. 15 1/2, par. 22.49)
(Source: Laws 1945, p. 335.)