Opponents to the plan are concerned about the environmental disruption that would be caused by new airport construction and the roads that would be needed to support it. They also point out that Gary/Chicago International Airport in Gary, Indiana already exists, is closer to Chicago than Peotone, and is already undergoing expansion to support heavier use with minimal environmental impact. Politicians opposing the Peotone airport plan include former Chicago Mayor Richard M. Daley, former Gary Mayor Scott King, Indiana Governor Mitch Daniels, and Representative Pete Visclosky from Indiana.