The federal government today gave the green light for the construction of a new toll road that would replace the existing Elgin-O'Hare Expressway and also skirt the western edge of O'Hare International Airport.



The formal approval from the Federal Highway Administration and Federal Aviation Administration, known as a record of decision, is the last step in the project's environmental impact review process.



The action, which was expected, allows the Illinois Tollway to proceed with the $3.6 billion project, which will take an estimated 12 years to complete.



The project will include construction of an all-electronic toll road bypassing O'Hare along its western border and linking the Jane Addams Memorial Tollway (I-90) and the Tri-State Tollway (I-294).



In addition, the existing Elgin-O'Hare Expressway will be converted into a toll road. It will be widened and extended east along Thorndale Avenue to connect to the O'Hare bypass.



rwronski@tribune.com

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