There is an App that the FAA endorses called "B4UFLY" It has all the restricted airspaces recognized by the FAA. Note that DuPage County IL has a "No Drone/No RC Aircraft" countywide restriction except in designated locations. There is no restriction shown for DuPage County and the FAA says this is the source for where you can & can't fly. If you were to get busted, it would become an interesting legal case. (I've already had my run in with Beth DuPage County Forest Preserve police, but we agreed to disagree & no ticket was issued.)
Remember local jurisdictions aren't allowed to pass their own laws retaining to railroads. Can't see where this would be much different.