Delays to Victoria's $6.7 billion West Gate Tunnel have left 137 workers without a job amid concerns the Government's 2022 deadline for the project is unachievable.

Key points: Tunnelling contractors have been left without work due to ongoing delays

Tunnelling contractors have been left without work due to ongoing delays PFAS contamination has halted tunnelling works

PFAS contamination has halted tunnelling works The union is calling for the project builders to redeploy workers to other projects

Soil contaminated with the industrial chemical PFAS has halted tunnelling work and led to a growing impasse between operator Transurban, the project's builders and the Victorian Government.

Today, 137 tunnelling workers on the project are being told they no longer have a job.

A Transurban spokesperson said the CPB John Holland Joint Venture, which is building the tunnel, had been working through a consultation process with affected tunnelling workers and was looking to support people wherever possible through redeployment or redundancies.

"We're committed to delivering this project safely and as quickly as possible and continue to work with all project parties to finalise plans for tunnelling and spoil disposal," the spokesperson said.

Many of the workers moved interstate to work on the project, including tunneller Garry Vereb, 62, who relocated from Queensland with his wife.

"The whole thing has been so poorly handled," he said.

Garry Vereb moved from Queensland to work on the West Gate Tunnel, and is now out of work. ( ABC News: Richard Willingham )

Mr Vereb said the Government should have been aware of the contamination risk.

"That was a betrayal of our trust," he said.

"We came here on good faith that we would be employed and we would have a job to do."

Tunnelling was due to start last year

Tunnel-boring machine "Bela" was due to start digging last July, but the State Government and the project's builders have struggled to find a solution after the toxic industrial contaminant was found.

PFAS led to the shutdown of the Country Fire Authority's Fiskville training college in 2015.

It has been linked overseas to an increased risk of some cancers, but Australian authorities deny the link.

The West Gate Tunnel is scheduled to be finished in 2022, but Mr Vereb said the deadline was unrealistic.

An artist's impression of the entry to the West Gate Tunnel. ( Supplied )

"Maybe the Andrews Government can come in on time … [if it does], I believe pigs might fly," he said.

Australian Workers Union shop steward Johnny Keys said the workers were being used as pawns by Transurban and the builder CBP and John Holland.

He suspected there were bigger issues than just contaminated soil holding up the project.

"[Victorian Premier Daniel Andrews] has been seen nowhere. He's not putting pressure on Transurban, or the joint venture. These guys shouldn't be losing their jobs," he said.

"It's a disgrace."

Speaking in Healesville, Premier Andrews said he hoped the workers — who were contractors and not employed by the Government — would be rehired soon.

"If I could intervene I would. All I'd say to them is there will be a couple of difficult months, but we'll have this drilling underway as soon as we possibly can," he said.

"We're not going to compromise safety, we simply can't do that."

Minister for Transport Infrastructure Jacinta Allan said the Government was "incredibly disappointed and angry" at the decision.

"The Government has made it clear it was our expectation that every effort was to be made to retain workers on this project or find them alternative [work]," she said.

Ms Allan said the workforce "could and should have been retained".

"There could have been opportunities for the workers to be maintained on the project or within the many other projects that CPB and John Holland are working on right now."

Opposition transport spokesman David Davis said the Government need to intervene to save the workers' jobs.

"They need to make sure that tunnellers who've come from overseas or interstate [and] moved their families to Victoria are not let go. I mean, this is bizarre."