Mame Reiley, a member of the Airports Authority board who chaired the committee that is overseeing the construction of the new Silver Line to Dulles, is stepping down.

Mame Reiley (Bill O'Leary/WASHINGTON POST)

Reiley has been battling breast cancer since 2010. Her resignation was effective at the close of business Wednesday.

Reiley is one of the longest serving members on the Metropolitan Washington Airports Authority board. She was appointed in 2002 by then-Virginia Governor Mark Warner and was later reappointed by then-governor Tim Kaine.

She has served for four years as chair of the Dulles rail committee, which is overseeing the building of the 23-mile stretch of Metro’s Silver Line through Tysons Corner to Loudoun County.

Dennis Martire, another MWAA board member, said Reiley’s departure is a loss for the board.

“She has shown exceptional leadership on the board, and to lose someone with the institutional knowledge she has is a blow to our board.”

He said McDonnell will be able to appoint someone to fulfill Reiley’s seat. She had about two years remaining in her six-year term.

A phone call and e-mail to the Virginia Secretary of Transportation were not immediately returned Thursday night.

McDonnell has pushed for getting two people he picked and wants appointed to the MWAA board but has been meet with resistance from some on the board.

Congress passed legislation that increased the size of the board from 13 to 17, giving the state two additional seats, plus one each for Maryland and the District. Before the bill was passed, Virginia had five representatives, the District and the federal government had three, and Maryland had two.

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