Deep in the heart of the Cadia Hill goldmine, 1.4km below the surface, heavy machines dump loads of ore into a crusher. On the wall next to the crusher is a ventilation grate, which draws the dust in to a filtration plant and out of the mine’s main vent, “vent rise outlet 8”.
Until May this year, the emissions were vented straight from the ore crusher into the atmosphere. Newcrest, which owns Cadia Valley Operations, has since installed two “bag houses” that catch up to 1 tonne of dust an hour each when operational. The second bag house only came online last month.
The grey dust found in those bags is valuable and may still contain gold. The general manager, Mick Dewar, says they are still trying to decide if that dust will be sent offshore for processing to remove valuable metals, or if it will be dumped in the tailings dam.
Dewar, who led Guardian Australia on the underground tour of the Cadia east mine along with two other senior members of the mine’s staff, says the vent, known as VR8, is “high velocity and it’s coming from a high dust source”.
“It’s got the worst combination, if you like, for the things to be a compliance problem,” he says. “And this is why we got called out.”
‘You can be angry at us, but you’re safe’
Last month, the NSW Environment Protection Authority revealed that sampling in May showed VR8 was emitting dust at more than 11 times the limit of air pollution regulations. The EPA chief executive, Tony Chappel, said the results were “completely unacceptable”.
Dewar says the conditions at the mine “weren’t great, weren’t representative, but the result is the result”.
The interim results of a second round of air monitoring data, collected in June when both bag houses were operational, showed pollution was within the regulatory limit.
A chemical analysis of the sampling done in May was not submitted to the EPA and the June results are not due in full until the end of the month. An earlier report, prepared for Newcrest by environmental and air monitoring consultants Ektimo in May 2022, found VR8 was emitting lead at a rate of 1.3g a minute.
The EPA has been investigating the goldmine since May 2022, when it issued Newcrest’s Cadia Holdings Pty Ltd with a draft pollution prevention notice and a draft licence variation regarding its management of emissions of dust and other pollutants. It followed an investigation of household rainwater tanks by residents that found one in three rainwater samples tested had unsafe levels of lead.
Last week, Dewar told Guardian Australia that an independent chemical analysis commissioned by Newcrest had identified the goldmine as a potential source of some of the lead found in residential rainwater tanks, but said the isotopes only matched lead found in tanks with lower concentrations of the heavy metal.
Dewar says that chemical analysis, which has not yet been released, and an analysis by the Australian Nuclear Science and Technology Organisation (Ansto), released last week, should reassure the community that “the air out there is actually safe … the water is safe too”.
“You can be angry at us for what we’re doing, but you’re safe,” he says. “We’ll meet with the residents every month and in a couple of months, we’ll have nothing to talk about, and that’s the truth.”
But residents who spoke to Guardian Australia aren’t buying Cadia’s claims.
“What we have here is a large company who pride themselves on being a good corporate citizen and a good community neighbour,” says Alison Simmons, who lives less than 10km from the mine at Forest Reefs.
“[But] the perception here is that production targets outweigh environmental concerns. Now, that is not a good corporate citizen. That is a very bad community neighbour.”
Visible dust clouds
Before stepping up into his current role as general manager in February, Dewar was leading the team that built the extraction fans for VR8. Within a few weeks, he says, they noticed the impellers were wearing out “really aggressively” and there was “a lot of slurry buildup”.
“We had a lot of wet stuff just landing on the roof, just mud basically falling out at the top of the fan,” he says. “It took a while to start to register that, hey, not all of this stuff might be hitting the ground here; there might be some stuff that’s actually getting into the atmosphere.”
The community noticed and made complaints. In early 2022, Newcrest commissioned an independent air quality audit from Zephyr Environmental, which found VR8 was emitting dust at seven times the regulatory limit.
When the vent is working correctly condensation will saturate the dust and cause much of it to drop out, but in recent months, Dewar says, that hasn’t been happening. A few weeks ago, he says, the emissions from VR8 were visibly different to the water vapour coming from other vents. “You can’t argue with the community when they can see it,” he says.
But Dewar says he is “very confident” that the mine is now operating in compliance with its licence conditions. He claims VR8 has been expelling “clean air” since the second bag house was fixed in June.
Sarah*, a local nurse and mother of two, can see the plume of emissions from the mine from her home 5km away “almost every day”. She often finds white dust that had settled on her property.
“We noticed significant discoloration of our water,” she says. “We’ve got gutter guards on our tanks, so it’s not leaf litter. It’s coming from the dust in the air that’s landing on our roofs and going into our tanks.”
Newcrest has previously arranged for one of her rainwater tanks to be cleaned out and even pressure-washed the house. But she still worries about the water. “I bathed my children in that. We all drink the water,” she says.
Sarah’s property is one of at least 60 from which the EPA has collected water samples as part of its water testing program. It has also been testing bore water and plans to sample creeks and dams.
Newcrest maintains that the mine is not causing a rise in air pollution. Dewar says that it’s understandable that the community is concerned.
“They can see the dust; they know we’ve had dust problems; they know we’ve got a compliance issue,” he says. “It’s perfectly understandable when they go and test tanks and they see that they made the connection. We get it. But we’re deadly serious that we’re in compliance now and we will stay there.”
More data needed on pollution
Some experts have questioned whether the tests commissioned by the mine have asked all the right questions.
The Ansto report sampled fine particulate matter (PM2.5) at four sites near the mine – Millthorpe, Mandurama, Panuara and Orange – over a 12-month period. PM2.5 particles are often measured in air quality tests because they are small enough be breathed into the lungs. The report found levels below the National Environment Protection Measures guidelines.
Dewar says the results may not be “what [residents] want to hear, for some of them, but it’s the data”.
But Dr Ian Wright, an academic at Western Sydney University who helped conduct the community-driven rainwater tank testing, estimates that the particles collected from the tanks were much bigger.
“The dust particles we saw in the samples were very heavy,” Wright says.
The Ansto research team told Guardian Australia that it was nominated by community members and commissioned by Cadia to conduct an independent, scientific study, which only measured the PM2.5 mass in the samples collected.
“The scope of the study did not include assessing previous emissions studies commissioned by the CVO mine, or ongoing Cadia-operated sampler data,” Ansto says.
Wright says while focusing on PM2.5 makes sense for general air quality monitoring, it did not address the concerns raised by residents which related to particles washing into their rainwater tanks. He suggested the monitoring should be widened to include a survey of larger particles.
“No one cares about particle size when you’re looking at the fallout on paddocks, roofs and contamination of drinking water,” he says. “It’s just not relevant.”
Wright is one of nine members appointed to the EPA’s independent panel of experts last week, who will be providing advice as its investigation into the Cadia goldmine continues.
“I will be pushing very hard for, within that panel, to get the EPA licence to start documenting this,” he says. “It doesn’t matter what the particle size is and we should have a breakdown.”
‘People are really pissed off’
Wright also joined some residents in criticising the size of fines levied against Newcrest in the past.
In 2022, the EPA issued two fines to Newcrest over the Cadia goldmine: $15,000 in March for failing to conduct continuous air quality monitoring in the previous two years; and another $15,000 in August for dust pollution.
That is equivalent to 0.001% of Newcrest’s underlying profit in 2022.
Alison Simmons, who has lived at her Forest Reefs farm for 30 years, says it’s a “laughable” amount. “It’s not a deterrent, it’s farcical.”
Simmons says while the EPA has acted swiftly since water quality concerns were raised this year, and particularly since some residents began getting their blood tested, but that overall the regulator’s response “fell short of my expectations”.
She says the community’s “tolerance is being tested”. “People here are really pissed off about this,” she says.
Emma* moved away from Forest Reefs earlier this year, but had lived in the region for 30 years. Her farm was on land covered by one of several exploration licences held by Newcrest, which cover a total area of 200 sq km.
“There are drill sites on it … They’ve explored all the way out there for gold and it’s capped,” she says. “Cadia’s grip on the community extends much further than I think generally people realise.”
She also recently had her blood tested for heavy metals. Her toxicology results were not concerning.
Both Emma and Simmons have friends who work at the mine. They say people are reluctant to criticise it for fear of losing jobs, community funding or other commercial opportunities.
“We’re surrounded here by people who currently work at the mine, or who live in a mining household,” Simmons says. She claims those who do business with the mine could have a conflict of interest. “It’s a pretty effective cone of silence.”
Emma says that conflict can include those who have an exploration overlay on their property. “The amount of control they’ve got over farmland in the area is significant,” she says.
Simmons says she wants to see the mine held accountable.
“I love this area,” she says. “We put down roots here 30 years ago, we’re surrounded by the beauty of nature. Make them toe the line – everybody else has to.”
* Names have been changed
