Four Democratic members of Virginia’s congressional delegation are calling on Defense Secretary Robert Gates to delay the move of 6,400 defense employees to the Mark Center — located at the already-congested intersection of I-395 and Seminary Road in Alexandria — by one year.

“The department [must] consider all options to avoid the severe disruptions to traffic that will affect the nearly 200,000 commuters including Army personnel who travel on I-395 daily,” wrote Reps. Jim Moran and Gerry Connolly along with  Sens. Jim Webb and Mark Warner.