Here come da tunnels, page-40

• Naturally occurring, potentially acid sulfate soil associated with the presence of specific geological formations, such as Coode Island Silt, Werribee Formation and Brighton Group, that may become oxidised during construction – with these formations most likely to be found at the western portal, eastern portal and Arden station sites and in sections of the tunnels between CBD South station and the eastern portal
• Naturally occurring, potentially acid sulfate rock, which is prevalent along most of the alignment

NAG is only 1 1/2 hour drive from the CBD without rumbling through suburban streets

Can it get any sweeter?