The Middle Tracks at the National Airport Metro Stop

I see that the middle set of tracks at the Airport stop are pretty well filled in with ice. It made me wonder – does this set of tracks get used when it’s not a dumping ground during times of inclement weather? I haven’t been riding the rails here long enough to know this and certainly don’t get as much use out of the airport as some other folks do. I am curious whether the rust on the tracks is from a long period of not being used or if it’s from the melting ice sitting there.