McLEAN, Va. (AP) — Fairfax County officials will be answering questions from the public about the multi-billion project to extend Metrorail through Tysons Corner to Dulles Airport.

Two leaders on the Dulles Rail project from the county’s Department of Transportation will discuss various aspects of the plan Friday in an online chat.

Phase One, which runs through Tysons to Reston, is more than halfway complete and is scheduled for completion by the end of 2013. Fairfax and Loudoun counties are currently considering final approval for Phase Two, which will cost an estimated $2.7 billion and extend the line to Dulles and eastern Loudoun.

Phase Two would rely heavily on increased tolls on the Dulles Toll Road. Projections show one-way tolls could triple to $6.75 by 2018.

Questions can be submitted online here.

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