The West Australian Department of Mines and Petroleum is investigating evidence of asbestos contamination at Rio Tinto's West Angelas iron ore mine.
The asbestos was reportedly found in landfill materials brought in from the nearby Holcim quarry at Newman, according to the ABC.
A Rio spokesperson confirmed the appearance of asbestos at the site, adding that the levels were below safety exposure limits, and that all workers were immediately informed of the discovery.
In the wake of the incident Newman's Holcim quarry voluntarily suspended its operations.
The DMP will release a report tomorrow.
BHP has also reportedly suffered from an asbestos contamination at its Jimblebar iron ore mine.
According to the CFMEU it has been investigating worker claims of asbestos contamination, stating that workers may be exposed at the site.
The mine itself has been made aware; their position on the subject was until they receive confirmation from further testing, they were going to continue to use this," CFMEU safety officer Steve McCann told the ABC.
"Now that borders on negligence as far as I'm concerned.
"Even the risk of contamination or exposure to the workers on that site, they should at least stop production until such time as they have confirmation that the material they're using is safe."
This is not the first time there has been an asbestos scare in the Pilbara.
Late last year around ten workers were exposed to it after carrying out maintenance work in Port Hedland.
According to the Maritime Union of Australia crew from Teekay Shipping, a BHP contractor, were exposed to chrysotile, or white asbestos, while removing gasket material on the Star Voyager last month.
Two weeks earlier Teekay workers at Port Hedland walked off the job after asbestos was found in the gasket joining material on another tug, the PB Fitzroy.
Fair Work Australia ordered an end to the strike on 29 August, but with the proviso Teekay “put in place precautions to minimise the risk of exposure to its employees”.
After the ruling the MUA and Teekay agreed to the introduction of an asbestos management plan.
MUA assistant branch secretary Will Tracey said the Teekay crew were exposed to asbestos for up to 24 hours after the Star Voyager maintenance.
He said at least one worker had also exposed their family to asbestos after returning home from work in contaminated workclothes.
A BHP Billiton spokesperson said it was aware some of its Port Hedland tugs contained small amounts of asbestos.