One million tonnes of West Gate Tunnel project soil decontaminated at facility at Bulla in city’s north

One million tonnes of soil dug from the West Gate Tunnel project was decontaminated at a special facility— only for it to be found it wasn’t toxic at all.

One million tonnes of soil dug from the troubled West Gate Tunnel has been trucked to a special decontamination facility in Melbourne’s northwest — but none of it has been toxic.

The Hi-Quality tip in Bulla, near Sunbury in Melbourne’s northwest, was converted into a special storage and treatment hub to deal with soil containing industrial chemicals such as PFAS.

Low levels of the potential toxic substance were detected in soil during early works for the road and workers downed tools in 2019, triggering a lengthy project shutdown and legal battle over who would pay for massive cost overruns.

The West Gate Tunnel project soil is disposed of in Bulla. Picture: Alex Coppel.

Last year a settlement was reached — costing taxpayers more than $1.7bn and blowing the project’s total budget by $4.1bn — following the approval of the Bulla site.

Tunnelling has been underway since March, with massive boring machines currently under Yarraville and more than 40 per cent through the job — excavating a mammoth one million tonnes of spoil.

While some soil has had traces of industrial chemicals including PFAS, levels were under “permitted” EPA guidelines.

West Gate Tunnel Project acting chief executive, Peter Lellyett, said the specialist-built facility in Bulla where the soil is trucked “operates around the clock and has been engineered to manage even higher levels of PFAS than what has been found so far”.

“In the few cases where PFAS has been detected in the soil that has gone to Hi-Quality from the West Gate Tunnel Project, it has been at much lower levels than what is permitted,” he said.

The facility at Bulla includes 59 “engineered holding bays” where soil is dumped before treatment, which includes being ‘washed’ using a purpose-built water treatment plan that removes contaminants.

There are 59 engineered holding bays at the Bulla site where soil is dumped before treatment. Picture: Alex Coppel.

A 25-hectare containment cell “with multi-layer lining” stores leftover soil.

Despite rigorous safeguards put in place, nearby schools and communities were in uproar when they learnt the Andrews Government planned to dump potentially toxic soil on their doorstep.

Ombudsman Deborah Glass criticised the process, saying that communication with residents was poor and the Environment Protection Authority was “pressured” to find a solution to the West Gate Tunnel soil crisis.

The cost of setting up the facility and disposing of the project soil is understood to be in the hundreds of millions of dollars but has been absorbed into the overall project budget — which is now a colossal $10.8bn.

At the time the project was proposed by tolling giant Transurban its cost was estimated at $5.5bn.

About three million tonnes of soil is expected to be sent to Bulla from tunnelling, while the

road’s opening date has been pushed back to late-2025

Early WGT opening hopes

Builders of the West Gate Tunnel are trying to claw back some of the time they’ve lost on the troubled project, possibly bringing forward its opening date.

Tunnelling of the link, which will connect the West Gate Freeway to CityLink and ease congestion on the West Gate Bridge, finally began this year after costly delays that blew out its budget from $6.7bn to $10.8bn.

The road was initially due to open this year, but a settlement on cost overruns and the disposal of contaminated soil – which included taxpayers coughing up more than $1.7bn – altered the deadline to the end of 2025.
In an update on Transurban’s results for the previous financial year, released on Wednesday morning, Transurban chief executive Scott Charlton said the contracted builders, John Holland and CPB Contractors, were hoping to rein in some of the lost time.

Transurban chief executive Scott Charlton says about 40 per cent of the major work on the West Gate Tunnel is now complete. Picture: Andrew Henshaw

“We are still forecasting it to finish by the end of ’25, and obviously the contractors are targeting earlier completion and we are trying to help them do things where they could potentially achieve that,” he said.
With tunnelling finally underway, Mr Charlton said about 40 per cent of the major work was now complete and some of the major steel structures were in place.
“We are really pleased with how it’s progressing,” he said.
Transurban notes in its presentation to shareholders that tolling revenue would be lost due to the tunnel opening late, but Mr Charlton said the amount would not be disclosed.
Overall, the company was buoyed by people returning to their cars after pandemic lockdowns, with traffic numbers at the end of the financial year higher than at the same time in 2019.

West Gate Tunnel works near Grieve Parade. Picture: Andrew Henshaw

“Ongoing concerns over personal health and safety are contributing to that shift. If the trend continues, road networks are likely to face further pressure,” its market update says.
While people were only travelling to workplaces an average of three days a week, the company says the pandemic and concerns about public transport may be leading to them opting for private vehicles.
“Greater flexibility in work arrangements may lead to greater use of private transport for commuters,” it says.

In Melbourne, CityLink tolling revenue roared back to life and lifted 17.3 per cent to $722m. The company said it was well-insulated from inflation and interest rate shocks, with most of its tolling prices adjusted by CPI.

Flexible work arrangements brought about by the pandemic also provide an opportunity to “manage demand on transport networks”, the company says.
This could be done “by shifting commuters away from traditional peak hours” due to more flexible hours.

Without this, congestion is likely to cause headaches due to the higher number of people driving cars rather than catching public transport to work.

Originally published as One million tonnes of West Gate Tunnel project soil decontaminated at facility at Bulla in city’s north