The West Gate Tunnel Project is a much-needed project for Melbourne’s west to provide an alternative to the West Gate Bridge and take thousands of trucks off residential streets.

To build the West Gate Tunnel approximately 1.5 million cubic meters of soil will need to be removed.

Digging up this amount of soil will be a 24/7 operation at our tunnelling hub in Yarraville.

Work has started on a purpose-built facility at Hi-Quality Group’s Sunbury Eco-Hub that will manage and dispose of soil excavated by the tunnel boring machines on the West Gate Tunnel Project.

Hi-Quality’s site was recommended by CPB John Holland Joint Venture, Transurban’s builder, following a comprehensive assessment of the technical specifications and environmental protection capabilities of three potential sites in outer Melbourne.

To enable tunnel boring to get underway as soon as possible, Transurban will advance funding so construction can commence at Hi-Quality facility, which is expected to generate up to an additional 200 jobs and take around six and a half months subject to weather conditions.

West Gate Tunnel Project soil management diagram

How tunnel soil gets taken out of the ground

As our Tunnel Boring Machines (TBMs) dig underground, excavated soil is moved via a 15km covered conveyor system that crosses high above Somerville Road to our purpose-built shed located on Whitehall Street, Yarraville.

It is then placed in storage areas, before excavators load it into covered and lined trucks for safe and secure transport to a disposal facility.

All relevant EPA Victoria and WorkSafe Victoria requirements will be met every step of the way to protect the community and workers from the moment the soil is dug up to when it’s transported and disposed of appropriately.

Safely managing any soil

Testing shows the levels of PFAS in the groundwater from soil extracted by the tunnel boring machines is expected to be low and at safe levels for the community and the environment.

Testing also indicates levels of PFAS between zero and 0.7 micrograms per litre – which is between detectable limits and water that is safe to swim in.

Despite these findings, the Victorian Government has a strong track record of taking a conservative, safety focused approach to the management of PFAS. When managing soil, our first priority is to make sure protections are in place for the community and workers in line with EPA and WorkSafe requirements.

Safely transporting soil

The trucks that take tunnel soil away from West Gate Tunnel Project worksites are sealed and fully covered so there is no dust or soil dropped on the road.

Other safety measures can include hosing down the truck and its wheels before it leaves site, and loading the truck in an enclosed shed.

All trucks are approved by the EPA, fully assessed for roadworthiness and compliance with noise and emission limits and follow approved truck routes to get to a disposal site.

Drivers are fully trained and GPS technology in the trucks will allow monitoring to ensure truck routes are adhered to.

Workers won’t need to handle any tunnel soil – from the moment it’s dug out by the TBM its movement is completely automated until it is placed into trucks to leave site.

Download the fact sheet.