How the freight rail connections with upstate all fit together is kinda mysterious. The car float is very limited, but it might carry the garbage. The only other way out of East Williamsburg is via Queens and the Hell Gate, and that would of course involve sharing track with Amtrak's passenger trains.

Hunts Point is connected to the broader freight network, though, so I'm reasonably certain there's a connection between the NYA (LIRR freight operations) and the outside world that doesn't involve the car float. Operationally it might be kinda limited, tho.