Illinois Wilderness Act of 1990

Illinois Wilderness Act of 1990 - Designates the following lands in the Shawnee National Forest, Illinois, as components of the National Wilderness Preservation System: (1) Bald Knob Wilderness; (2) Bay Creek Wilderness; (3) Burden Falls Wilderness; (4) Clear Springs Wilderness; (5) Garden of the Gods Wilderness; (6) Lusk Creek Wilderness; and (7) Panther Den Wilderness.

Designates the East Fork Area and the Eagle Creek Area of the Shawnee National Forest as special management, mining, and prospecting areas. Sets a time limit for such prospecting and mining. Provides that these areas shall be designated as wilderness and components of the National Wilderness Preservation System 20 years after enactment of this Act (or eight years after enactment if no prospecting for fluorspar and minerals has been done).