Queensland’s powerful construction union has called for ministerial intervention to stop work on one of its key Cross River Rail tunnelling sites until concerns about the potential release of dangerous silica dust can be probed by the safety regulator.

Workers downed tools one weekend, between June 18 and 21, while the Cross River Rail Delivery authority and major contractor CPB addressed what the CFMEU said were long-running issues at the Woolloongabba site involving dust from the conveyor belt carrying tunnel spoil to the surface.

Construction work on the Cross River Rail Gabba station in January.CREDIT:ATTILA CSASZAR

Recent footage taken from within the site, seen by Brisbane Times, showed workers wiping dust from surfaces after the belt had been in operation for 20 minutes. In separate videos taken from outside at night, plumes of dust can be seen emerging from the large shed erected to contain the massive tunnelling operation.

The union says the dust issue was occurring because water pumps, meant to dampen the rock transported by conveyor belt from deep beneath the bedrock, were not being used in an effort to lighten the load required to be carried away by trucks.

Branch president and health and safety co-ordinator Royce Kupsch said the incident was evidence of “dangerous cost-cutting” from the contractor whose list of total regulatory enforcement notices was approaching that of the trouble-plagued Toowoomba Bypass, on which work was forced to stop.

“We shouldn’t need the union to intervene on day-to-day health and safety matters on a project of that magnitude,” Mr Kupsch said. “We’re mortified that this sort of event was allowed to go unchecked.”

Dust being released into the air from the Woolloongabba Cross River Rail worksite.

Greens South Brisbane MP Amy MacMahon, whose state electorate covers the site and has held meetings with residents, has written to Transport Minister Mark Bailey urging him to halt work while an investigation into the presence of silica dust can be carried out.

“The safety and wellbeing of workers and nearby residents should be the absolute priority for the government, but instead we’re hearing reports of dangerous silica dust and cost-cutting at the Gabba Cross River Rail site,” she said. “It’s unacceptable”.