The station entrance has now reopened.
The Seattle-based carrier will offer a daily flight to the Emerald City.
A spokeswoman said a conductor slipped as the train was approaching the Dickerson station.
Route 1 is closed in both directions from Slater’s Lane to First Street in Alexandria due to two fallen electrical poles in the road.
Earlier delays because of a train malfunction are clear.
Trains were stopped at Fort Totten.
Crews are waiting for asphalt to cool and should be finished working on southbound lanes by midday Thursday.
Authorities reopened the highway following the 6:10 a.m. accident, just before Route 97, also known as Georgia Avenue.