What project is a rail infrastructure project that includes a twin rail tunnel and the building of the Arden railway station?  
Arden railway station, Melbourne: Arden railway station is a planned station to be built as part of the Melbourne Metro Rail Project. Melbourne Metro Rail Project: The Melbourne Metro Rail Project (marketed as the Metro Tunnel and formally known as the Metro Rail Capacity Project), is a metropolitan rail infrastructure project currently under construction in Melbourne, Australia.
i don't know