Workers and the public are facing unacceptable health and safety risks from toxic substances unearthed during work for the West Gate Tunnel, according to the union representing many of the workers on the project.

Tests on soil excavated from tunnel work sites, particularly those around Coode Island, have shown contamination with PFAS, a dangerous chemical substance associated with cancer clusters at the CFA’s Fiskville site, according to results seen by Star Weekly.

Tunnel authorities say proper safety procedures are in place to protect the public and workers, but the CFMEU says hundreds of tonnes of the soil stockpiled alongside Footscray Road for weeks posed a health risk yet were only moved after pressure was applied.

Union spokesman Jack Kerr said contractor CPB John Holland Joint Venture had been lax with regard to its management of contaminated soils and also left soil with asbestos in it exposed near residential properties in South Kingsville last week.

The CFMEU has launched a series of mobile billboards and a dedicated “toxic tunnel” webpage outlining its concerns.

CPB John Holland referred Star Weekly’s request for comment to the West Gate Tunnel Authority.

A WGTA spokeswoman confirmed that low levels of PFAS and small amounts of asbestos had been identified in soil being dug up in former industrial areas, but said all contaminated materials were being appropriately managed.

“Finding contaminated soil is part and parcel of construction in urban areas, especially in former industrial areas,” she said.

“The construction contractor CPB John Holland Joint Venture has been in ongoing contact with the EPA and WorkSafe to ensure the contaminated soil is being handled appropriately and measures are put in place to protect the workforce and the community.”