There was a plan to stop Sydney tunnel workers from being killed. It was ignored for five years

A major construction company gave the safety regulator a detailed plan to eliminate the threat of deadly silica dust to tunnelling workers, but warned it would be expensive and lead to project delays.

Nearly five years later, the plan provided to SafeWork in May 2020 is sitting unused despite NSW Premier Chris Minns declaring the health and safety of tunnelling workers on multibillion-dollar public transport infrastructure works was “more important to us than the project”.

Tunnel workers are exposed to high levels of crystalline silica.Credit: Kate Geraghty

Thousands of workers tunnelling through Sydney’s sandstone heart have been repeatedly exposed to dangerously high levels of deadly silica dust. Fears of a latent public health disaster compounded after the Herald revealed 13 workers, including a 32-year-old, on the M6 Stage 1 had been diagnosed with the incurable lung disease silicosis since the project began in late 2021.

A SafeWork investigation into the employer, construction firm CPB Contractors, is continuing. But the regulator has been criticised by the Australian Workers’ Union for failing to take meaningful action despite knowing about hazardous levels of silica dust for several years.

A 2023 investigation by the Herald, The Age and 60 Minutes exposed serious health risks for tradespeople working with engineered stone, prompting bans on manufactured stone benchtops, panels and slabs containing at least 1 per cent silica.

Curtin University research from 2022 forecast up to 103,000 Australians will develop silicosis after exposure to the dust at work.

John Holland’s May 2020 presentation had a five-stage hazard management plan. It urged reducing the reliance on personal protective equipment, which sat at the bottom of the risk management pyramid and offered the “lowest level of protection” for workers.

The elimination of silica dust was described as “the goal to aim for”. The presentation contained four suggested methods, including reducing worker shifts from 12 hours to eight, and upgrading tunnel ventilation.

Adopting the approach, however, would have negative impacts on productivity, costs and ultimately project delivery, the presentation warned. Stopping concurrent excavation activities, another strategy suggested, would have “significant adverse overall project program impact”.

The presentation said the associated costs of reducing silica exposure should be incorporated into the tender for “future projects”.

The second tier of the risk management strategy was substituting safer tunnelling methods for more dangerous ones. It urged the mandated use of gigantic machines known as tunnel boring machines (TBMs) in favour of mined tunnelling, which relies on cheaper-to-run but hazardous road headers. In a submission to a parliamentary inquiry in October, the AWU identified NorthConnex, the M6 Stage 1, WestConnex and the Western Harbour Tunnel as being reliant on road header machines.

As he announced the completion of a key stage of the Western Harbour Tunnel on Monday, Minns said he was unaware of any cases of silicosis on this particular project but said the safety of tunnel workers would have the “highest priority in the government”.

“There has been [diagnoses of silicosis] on the M6 and that’s a major, major concern for us. I want to make it clear that the health and safety of the workforce on these major public transport projects is more important to us than the project,” he said.

“We want to make sure that people can work on these projects, get home safely to their loved ones and work in the industry or whatever they want to do for decades into the future.”

Despite the comprehensive safety plan, in October 2020, internal correspondence revealed air quality testing results on the WestConnex Haberfield site, managed by John Holland, had “grossly exceeded” the Workplace Exposure Standard by “factors of 13 and 14”.

The email questioned why “operations persisted in the absence” of effective safety controls.

“The results validate your decision during the inspection, specifically to expedite staff from the work area due to the impact of RCS dust generated by road header operations in the adjacent tunnel,” the email stated.

Unions NSW secretary Mark Morey said the presentation demonstrated contracting companies were prioritising “profit over safety”.

“For some of these companies, they factor workers getting diagnosed with silicosis as the cost of business,” Morey said. “They want to get this stuff done as quick as possible.”

Work Health and Safety Minister Sophie Cotsis did not respond to questions regarding whether she was aware of the risk management plan, if the government had explored implementing any of the elimination or substitution strategies outlined in the presentation or had been briefed on costs of introducing the safety measures.

Instead, she took aim at the former Coalition government, saying their neglect of the safety regulator was a “disgrace”, and said SafeWork “needs to be more proactive and a tougher cop on the beat when it comes to protecting workers from silica exposure”.

“Under our government, it is now mandatory for companies to notify SafeWork when silica levels exceed limits,” she said, adding that a silica tunnelling taskforce and compliance team had been established.

SafeWork NSW acting deputy secretary Trent Curtin said the regulator “encourages industry” to share safety practices among one another to improve the standard across industry. He listed various risk control measures used on tunnelling projects.

“[Companies engaged in tunnelling projects] hold responsibility for determining the most appropriate methods for providing safety systems on each project,” Curtin said.

“The hierarchy of controls always encourages elimination of risk to be considered in the first instance. However, if cutting sandstone is a requirement of the project, alternative means of controlling the risk must be implemented as the risk of RCS is inherent when cutting through sandstone.”

A John Holland spokeswoman said all risks associated with tunnelling were taken seriously, and the company complied with all relevant work health and safety regulations. She noted the use of various dust control strategies employed by the company, including high-tech purifying respirators.

“Key controls outlined in the 2020 presentation are in place on projects where they are practicable and will make significant difference,” she said.

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