Metro officials say contractors building the new Silver Line are behind on some key items, which could lead to further delays for the project.
Rob Troup, Metro's chief of operations, told reporters Monday that contractors agreed to complete a checklist of 33 items before the line opens this summer. But Troup said the contractor and the Metropolitan Washington Airports Authority are behind schedule on about half the items.
The airports authority is overseeing construction of the new line, which extends Metro past Tysons Corner and will eventually reach Dulles International Airport.
The estimated cost of the first phase of the Silver Line is $2.9 million.
Troup declined to estimate when it will open but did not rule out that it will be running by the end of the summer.