Newcrest Cadia gold mine report confirms lead contamination connection to rainwater tanks
A report commissioned by a gold mine in central west NSW has confirmed lead matching its ore has been found in the rainwater tanks of Orange district residents.
The Human Health Risk Assessment (HHRA) was commissioned by Newcrest’s Cadia Valley Operations as part of a raft of regulatory requirements in the wake of the mine being found to be non-compliant by the NSW Environment Protection Authority (EPA).
Residents living in the mine district have been reporting dust events since 2018, when a dam holding mining waste called tailings failed.
The HHRA identified that point of use water, such as kitchen tap or tank tap, was the largest risk factor for heavy metal exposure and recommended that tank maintenance and monitoring “guidance is followed”.
Released to the public on September 1, the report concludes that the “potential risks to human health from emissions from CVO is low and acceptable”.
Lead matches Cadia
The report recaps independent studies commissioned by the mine to predict community exposure to date, including a tailings dust study, micro particle shed and lead fingerprinting work done by the University of South Australia.
Lead fingerprinting allows lead to be traced to its source using isotopic signatures.
Under the lead fingerprinting section, the report mentions that lead matching Cadia’s isotopic signature was found in 40 per cent of tank sludge samples collected by Newcrest.
This contradicts the mine’s July press release that stated there was “no evidence linking Cadia to the lead sampled in district rainwater tanks”.
In a statement, the report’s author said: “The information presented in the report is accurate based on available information at the time of completion of the report”.
Newcrest did not comment on why the HHRA report included information that contradicted previous communication by the company.
“The findings of the Human Health Risk Assessment conducted by Sage Environmental shows that Cadia is operating within established health standards, and the potential risk of emissions to human health is low,” it said in a statement.
Cadia Community Sustainability Network chair Gem Green said the changing messages had undermined the community’s trust.
“The process with Newcrest and Cadia over the last several months has completely destroyed the relationship with the community,” Mrs Green said
Twice state average
Using national health data from the Australian Bureau of Statistics, the assessment built a picture of the health of the Blayney and Orange districts that flank the mine and compared them to the wider region.
It did this to “accurately assess the potential impact of the CVO operations on the population”.
Statistics showed premature respiratory mortality rates for the Orange district were double the state average, and rates for Blayney were approaching double. Childhood asthma rates were also elevated.
Mrs Green said regulators weren’t doing enough.
“We have an entire district which appears to have significantly worse outcomes than surrounding areas,” Mrs Green said.
“In that context shouldn’t we expect the regulators to be doing everything possible to reduce emissions from all sources?”
In a statement, an EPA spokesperson said the Independent Health Risk Assessment was “extensive” and was under review by the watchdog.
“We required Cadia to have this assessment peer reviewed before its submission and the EPA will now have its own technical specialists review the report before it is provided to our independent expert panel for advice,” the spokesperson said.
“All reporting and monitoring provided by Cadia is closely interrogated by the EPA.”
Inquiry to look at communication
A parliamentary inquiry into the impacts of metal mining on health, water and air was announced in July with the committee expected to table its findings in November.
Greens MLC Cate Faehrmann, who will chair the inquiry, said it would closely examine how Newcrest had communicated pollution incidents to the community.
“This is critical to the committee being able to make recommendations to government, including where the law needs to be strengthened,” Ms Faehrmann said.
She said there was very little oversight when it came to mining companies’ public communication.
Water tank testing reveals heavy metal levels in residents’ drinking supply
July 28 2023: https://www.watoday.com.au/environment/conservation/water-tank-testing-reveals-heavy-metal-levels-in-residents-drinking-supply-20230728-p5dryv.html (Laura Chung)
Water samples from the properties surrounding one of Australia’s largest gold mines have failed to show the presence of widespread heavy metals, an investigation by the NSW environmental watchdog has revealed.
The NSW Environment Protection Authority (EPA) completed water testing for more than 85 properties in the Cadia Valley following concerns from residents that pollution from the mine was affecting their health.
EPA officers collected and tested water samples from household kitchen taps and water tanks and compared them to the Australian Drinking Water Guidelines. Most results from kitchen tap samples showed metal concentrations below the guideline values.
At two properties, lead was detected at or marginally above the accepted level of lead from samples taken in the kitchen tap, but water tank samples from the same properties were below guideline values.
Water tank samples showed six properties had levels of lead above the guideline’s values, while kitchen tap samples at these properties were below guideline values.
Once all tests from the water sampling program are completed, comparisons will be made with water sampling results previously undertaken by NSW Health, industry and the community. The EPA’s and NSW Health’s expert panels will consider the results.
Earlier this year, residents self-tested their tank water and found that, of the 68 samples, 15 were 10 times the safe lead level recommended by the Australian drinking water guidelines. As yet, there is no proven link between the mine and these complaints.
The EPA’s results come just days after a parliamentary inquiry was announced that will investigate the current and future impacts of gold, silver, lead and zinc mining on human health, as well as the effects on land, water and air quality. The inquiry will also examine regulatory framework, rehabilitation and decommissioning practices.
The EPA has also begun a separate extensive air monitoring program in the Cadia Valley.
In an update to investors earlier on Tuesday, Cadia’s owners, Newcrest, said a 12-month study conducted by the federal government’s Australian Nuclear Science Technology Organisation had found Cadia was meeting air quality standards for the mine’s surrounding region, and had highlighted that metals including lead, nickel, selenium and chromium did not exceed national standards, occurring at “very low levels”.
Mining inquiry to examine pollution impacts on health
July 26 2023: https://www.smh.com.au/environment/climate-change/mining-inquiry-to-examine-pollution-impacts-on-health-20230725-p5dr0c.html (Laura Chung)
The mining industry has been put on notice with a parliamentary inquiry to examine whether it is contaminating NSW residents and if regulations should be strengthened in response.
The NSW upper house inquiry will investigate the current and future impacts of gold, silver, lead and zinc mining on human health, as well as the effects on land, water and air quality.
The catalyst for the investigation arose from Central West residents’ concerns that pollution from the Cadia Mine – one of Australia’s largest gold mines, just outside Orange – was affecting their health, as reported by the Herald this month.
Some in the community believe dust from the mine has been allowed to drift across the region and pollute local drinking water. Residents tested their tank water earlier this year and found, of the 68 samples, 15 were 10 times the safe lead level recommended by the Australian drinking water guidelines.
Residents claim that children have broken out in rashes and their nails have become rough, ridged and slightly deformed. As yet, there is no proven link between the mine and these complaints.
A spokesperson for the Cadia Community Sustainability Network, a group that aims to work with the mine to find a way to live and work together, said the group welcomed the inquiry and looked forward to sharing their lived experiences.
Terms of reference for upper house inquiry
That Portfolio Committee No. 2 inquire into and report on current and future impacts of gold, silver, lead and zinc mining on human health, land, air and water quality in New South Wales, in particular:
a. The impact on the health of local residents and mine workers, including through biomagnification and bioaccumulation,
b. The impact on catchments and waterways, affecting both surface and groundwater destined for, local and town water supplies, including rainwater tanks, and on aquatic biodiversity,
c. The impact on land and soil, crops and livestock, including through biomagnification and bioaccumulation,
d. The adequacy of the response and any compliance action taken by the regulatory
authorities in response to complaints and concerns from communities affected by mining activities,
The effectiveness of the current regulatory framework in terms of monitoring, compliance, risk management and harm reduction from mining activities,
f. The effectiveness of current decommissioning and rehabilitation practices in safeguarding human health and the environment,
g. The effectiveness of New South Wales Government agencies to regulate and improve outcomes including:
- the measurement, reporting and public awareness,
- the provision of various protective materials,
- the ability to ensure the health of at-risk groups
- the suitability of work health and safety regulations, and the capacity to respond within existing resources,
- the adequacy of existing work, health and safety standards for workers,
- whether the regulatory framework for heavy metals and critical minerals mining is fit for purpose and able to ensure that the positive and negative impacts of heavy metals and critical minerals mining on local communities, economies (including job creation) and the environment are appropriately balanced.
i. Any other related matters.
2. The committee reports on its findings by 21 November 2023.
An investigation by the NSW Environment Protection Authority (EPA) into the residents’ claims is ongoing, with the mine’s owner, Newcrest, separately addressing the matter. The EPA has previously threatened to suspend the mine’s licence when the agency found “an unacceptable level of dust” coming from the mine.
In an update to investors earlier on Tuesday, Newcrest said a 12-month study conducted by the federal government’s Australian Nuclear Science Technology Organisation had found Cadia was meeting air quality standards for the mine’s surrounding region, and had highlighted that metals including lead, nickel, selenium and chromium did not exceed national standards, occurring at “very low levels”.
A Newcrest spokesperson said in response to the announcement of the parliamentary inquiry that the company welcomed the chance to talk about its operations.
“Mining safely, responsibly and sustainably is what our communities expect of us and what we demand of ourselves. Health and safety isn’t an option for our company, it’s a pre-requisite,” the spokesperson said.
Chair of the inquiry and Greens MP Dr Amanda Cohn said the inquiry would “examine whether there is an appropriate balance between the mining activities undertaken in this state and the health and wellbeing of communities and environmental areas impacted by those activities”.
Greens MP Cate Faehrmann said she expected strong engagement from multiple communities facing the prospect of heavy mining nearby.
“With one gold mine and a silver and lead mine having recently been approved in regional NSW, we must ensure that every measure is taken to protect human health and the environment. If this can’t be guaranteed, then the mines should not progress,” she said.
“Our regulatory framework protects global mining companies more than it does local communities and the environment. This is clearly unacceptable, and I certainly hope that we’ll come up with some recommendations to redress this imbalance.”
Claims from the Cadia community have spooked residents in Lue, about 30 kilometres from Mudgee. In April, the Independent Planning Commission (IPC) approved a new silver, zinc and lead mine. The Bowdens Silver mine owner – Silver Mines Limited – is set to produce about 3.4 million ounces of silver a year, as well as 6900 tonnes of zinc and 5100 tonnes of lead. Nearby McPhillamys Gold Project has also received approval from the IPC.
Lue resident and fifth-generation farmer Tom Combes said the inquiry meant small communities were being heard.
“I am delighted that [we’re] finally getting some reaction. We are fighting huge companies that are raising money through hedge funds. We are [funding] it through cake stores and trivia stores. That’s just not a fair playing field. The government needs to get more involved.”
The inquiry will also examine regulatory framework, rehabilitation and decommissioning practices – an issue that will become increasingly important as mines and other fossil fuel-intensive projects across Australia wind down. In the Hunter Valley alone, about 17 coal mines may close in the next 20 years.
The Herald reported this month that, despite strict regulations, there are many gaps in the mining rehabilitation. Western Sydney University professor Ian Wright, who has worked with residents near Cadia to test their tank water independently, said the inquiry was welcome news.
“The whole country is littered with closed mines that have inadequate rehabilitation,” he said.
The inquiry will provide its findings by November 2023.
Newcrest’s lead contamination claims ‘inconsistent’ with expert report findings, its author says
July 21 2023: https://www.theguardian.com/australia-news/2023/jul/21/newcrest-cadia-hill-lead-contamination-expert-report-findings (Fleur Connick)
Prof Brian Gulson says Cadia Hill goldmine could not be ruled in or out as the source of the lead, despite miner saying there was ‘no evidence’
An expert who analysed rainwater samples for possible lead contamination from Newcrest’s Cadia Hill goldmine says the company’s public interpretation of his report is “inconsistent” with his findings.
Newcrest commissioned Prof Brian Gulson from Macquarie University to conduct a lead isotopic analysis of water and sediment samples taken from 145 residential properties in the region and compare those with the lead found in the mine’s ore.
Commissioning the independent analysis was one of the conditions of a variation to Newcrest’s mining licence, ordered by the New South Wales Environment Protection Authority in June as part of an investigation into emissions from the mine. It followed reports by some community members that independent testing of their water tanks had found high levels of heavy metals, including lead.
The samples were collected in March and April. Guardian Australia understands that Newcrest provided 88 sediment samples and 16 water samples – 12 from rainwater tanks and four from the kitchen tap – to the University of South Australia for lead isotopic fingerprinting, a tracing technique used to identify the possible sources of lead.
Newcrest said that only the water samples that returned readings for lead above the Australian Drinking Water Guidelines of 0.01mg/L were sent for isotopic fingerprinting.
Gulson’s report analysing those results was published last Friday.
In a press release on Wednesday, Newcrest said the report found “no evidence” linking Cadia to the lead in the samples. It also claimed the report said 74 of the 88 sediment or sludge samples had “no correlation” to the lead samples taken from Cadia’s ore.
The remaining 14 samples exhibited “similar characteristics” to the lead samples from the mine’s ore and soil in the district, Newcrest said. Those samples also “recorded the lowest concentration of lead amongst all the sludge samples”.
“It’s clear to us in the [report’s] conclusion that there is no evidence linking Cadia to the lead that was found in the samples in the tanks that we tested,” the Cadia Valley Operations general manager, Mick Dewar, told Guardian Australia.
He added that the company does “note and acknowledge” Gulson’s comments in the report that the lead characteristics of the mine’s ore and the lead found in regional soil samples “could not be discriminated”.
“In addition to that, it was noted that there were no other markers or pointers suggesting that Cadia could be linked, such as a higher propensity of concentrations close to the mine,” Dewar said.
“There was no relationship there that suggests that the inability to discriminate between those two characteristics was anything other than no tangible link.”
Gulson, who is an expert in lead analysis, said the “claim about ‘no evidence’ is inconsistent” with his findings.
It is also inconsistent with Newcrest’s own fact sheet on the report, which says that due to the overlapping signatures “the source [of lead] could not be determined”.
“The ore field [lead] signature is in 12 of the 13 soil samples,” Gulson said.
He recommended a more comprehensive soil lead isotope testing program should be undertaken, given the “dominant” lead signature from the mine.
“You need more information, more data to try and get that relationship between either the mining operations or the soil,” he said.
Gulson said the report’s findings were inconclusive but did not rule out a connection to the ore from the mine. Of the water samples analysed, nine of 12 rainwater tanks samples and one of four kitchen tap samples were found to have lead isotopes matching Cadia’s ore.
Of the 88 sediment samples, 14 matched the lead isotope from Cadia’s ore and 74 were found to be consistent with lead “derived from a mixture” of sources, including the mine’s ore, rocks and soil, and lead from other contaminants such as petrol, batteries and paint.
But Gulson said “there was not enough data or hardly any data” to determine the source of lead found in the tanks.
“The important thing is that there was the [lead] fingerprint in some of the sludge samples [that] coincided with the ore field signature, but that didn’t necessarily prove that it actually came from the ore samples themselves,” he said.
“You can’t distinguish whether or not it’s the signature coming from the ore, the mining operation or out of a vent … or whether it’s soil that’s blown in on to the roofs and then finished up in the sludge. And at the moment, you can’t really say which is which.”
Newcrest is yet to provide the EPA with the chemical analysis of samples taken from the mine’s main crusher dust vent. That report is due at the end of July.
Due to his concerns around the accuracy of data and methodology in the report, Gulson recommended measuring a suite of samples with more precise methods to validate the data already accumulated.
Dewar said that while the company is “actively reviewing and considering” Gulson’s recommendations, it is “not inclined to pursue” them.
He said the company was taking “a broader viewpoint” of concerns about its emissions.
“In terms of narrowing the focus down to Cadia’s contribution to that lead, we’re satisfied with Prof Gulson’s report, with the Todoroski air modelling, with the Ansto modelling, with our boundary PM 10 monitoring and TDS modelling, that there is no evidence supporting that link,” Dewar said.
Taken together, Dewar said, those studies “strongly suggest that there is no evidence that we are creating a risk” to the community’s health.
“We think we’ve done the work to demonstrate that now,” he said.
The EPA told Guardian Australia it was currently reviewing the report, which will inform its regulatory activity. “Where appropriate, we will seek advice from our recently established expert panel to inform any future monitoring,” a spokesperson said.
Cadia Gold Mine near Orange ordered to fix dust pollution after heavy metals found in locals’ blood, water
May 30 2023: https://www.abc.net.au/news/2023-05-30/cadia-gold-mine-dust-pollution-deadline/102406512
Cadia Gold Mine in central western New South Wales has been given a series of deadlines to show it is complying with its obligations to prevent air pollution.
The Environment Protection Authority (EPA) has issued a final prevention notice, outlining the steps that must be taken to reduce emissions from the site and reassure the community.
The action was prompted by blood and water testing that was ordered by local residents and returned high levels of heavy metals like lead, nickel and selenium.
Cadia has just over a week to provide an interim report on emissions from an air vent which has been a cause of concern for residents.
It must then present a final report on sampling of this vent shaft two weeks later.
“The sampling within the vent has to be undertaken by highly trained skilled operators,” EPA executive director Carmen Dwyer said.
“That data will be provided to the EPA and we will draw our own conclusions from that data.”
The details of the final pollution prevention notice have heartened the local community but residents say they are concerned about the sampling methods being used.
“The community now has a timeline to watch and observe and see what the reports and the results come back as,” Cadia Community Sustainability Network chair Gem Green said.
“There are still a few muddy areas of who’s collecting what and how that will be processed and how that will be reported on.
“We’ll be keeping in close touch with the EPA to get a more definitive interpretation of how that will be done.”
The mine must simultaneously review its existing air sampling network and produce a report identifying suitable locations for more units to be installed in the district.
Ms Dwyer said the air monitoring sites would be decided in consultation with Cadia and the community.
“We have a look at dispersion modelling and climatic modelling and we talk to our experts about where that should occur,” she said.
“We’re also talking with the community to understand from their perspective with their local knowledge where should some of this stuff happen.
“The EPA is looking at what monitoring needs to occur within the community and sampling to provide that assurance to the community that are living with clean air and clean water.”
The Cadia Community Sustainability Network said many residents were still concerned about what to do to protect their health while the mine was given time to comply with its regulatory obligations.
“Health-wise, people are still very unsure what to do … we’re obviously encouraging them to get a health assessment conducted,” Ms Green said.
“We’re probably in a little touch of no man’s land at the moment, just with different government agencies sort of speaking with the community, and in the short term the community does need its water tanks cleaned and refilled.”
In a statement, a spokesperson for Cadia Gold Mine said it was cooperating with the EPA and already had work in progress to ensure it complied with the prevention notice.
“We do not compromise on people’s health and safety and remain firmly committed to meeting all our obligations in a way that is aligned with our values,” the spokesperson said.
EPA holds information session for residents as Cadia heavy metal contamination probe begins
May 23 2023: https://www.abc.net.au/news/2023-05-23/epa-gold-mine-heavy-metal-contamination-probe-in-nsw/102383008
One day after announcing an investigation into Cadia Valley gold mine, the Environment Protection Authority (EPA) has held a community information session in the village of Millthorpe, New South Wales.
More than 40 residents attended after learning that heavy metals had been discovered in people’s drinking water and bloodstreams.
Representatives from the EPA and NSW Health were on hand to hear concerns and provide advice at the session, which EPA chief executive Tony Chappel said was “extremely valuable”.
“They were appreciative we were there to listen to their concerns and discuss the actions we’re taking into the mine and their activities,” he said.
Most came seeking practical answers, including young mum Kayley Woods-Pendergast.
“I was wanting to know, are we safe to shower in [the water]?” she said.
As the mother of a toddler, Mrs Woods-Pendergast is especially concerned about exposure to lead.
She said she appreciated the session but hoped there would be more support to follow.
“I think what they’re doing today is a great start, but I think there’s definitely more they could be doing,” Mrs Woods-Predergast said.
For some, the opportunity to get tested was particularly important.
Stephanie Luke drove from Bathurst to learn how her rain-fed drinking water supply could be tested.
She said she had experienced unexplained health issues for several years.
“I’m quite curious about whether it’s got to do with environmental elements,” Ms Luke said.
“I’m about to have my water tested and I’m getting my bloods tested as well.”
Ms Luke was surprised companies such as Cadia were not legally required to submit weekly air pollution reports and said she felt let down by regulators.
“To hear stories of people, at their own expense, dragging authorities kicking and screaming and [for] the company to acknowledge that there’s an issue, I feel like we’re in some bizarre backwater,” she said.
Russell, who asked that his surname not be published, was only made aware there was an issue in his district that morning.
Because his household relies exclusively on rainwater, he was eager to arrange water tests that would establish a baseline for the quality of his drinking water.
Russell felt grateful for transparency the event gave the community.
“[That] we can have opportunities like this and find out from the people who are the checks and balances what’s going on, what’s proposed and if there’s a role that we can have to help, so that we’re not stopping progress, but that the progress is responsible,” he said.
EPA to probe Cadia gold mine after heavy metals found in residents’ blood, rainwater
May 22 2023: https://www.abc.net.au/news/2023-05-22/epa-probe-cadia-gold-mine-heavy-metal-contamination-claims/102374344
When her daughter started suffering severe skin reactions, Sophie Reynolds tried everything to try to ease the symptoms and find the source.
Ms Reynolds says the sores on her 10-year-old extended across her face and behind her ears.
Simultaneously, the family had been noticing plumes of dust blow onto their property from the direction of the Cadia gold mine near Orange, New South Wales.
When the family had the drinking water from the rainwater tank tested high levels of lead were found.
“As soon as we got those results, I said ‘I am not touching that water,'” Ms Reynolds said.
She started buying bottled water and travelled to Orange to shower and do laundry.
“Two days after I started washing [my daughter’s] face with the town water, the redness went,” Ms Reynolds said.
“Some of the sores were so deep, it took a week and a half [to heal].”
The Reynoldses are among a group of residents living near Cadia Valley Operations (CVO) who have been concerned about dust lifting off the site since 2018.
A section of wall on one of CVO’s tailings storages facility, which holds mining by-products, sustained damage in the same year.
In 2021 the mine’s expansion plans were approved and it vowed to make improvements to address concerns about dust.
Dozens of families have now had their blood and rainwater tested and the results show high levels of heavy metals such as lead, nickel and selenium.
‘It’s water vapour’
On Monday, the Environment Protection Authority (EPA) announced it has launched an investigation into the mine.
The EPA has issued a draft pollution prevention notice and a draft licence variation regarding the emission of dust and other pollutants from the site.
Chief executive Tony Chappel said he had also written to the NSW chief health officer asking for a full health-risk analysis to determine whether the mine dust was impacting the community’s health.
“Industry has strict obligations to meet clean air standards and currently Cadia appears to be falling well short of our expectations,” Mr Chappel said.
“Last week the EPA received new evidence from the community to suggest actions by the mine to reduce dust pollution have not been effective.”
The notices require the mine to retest a vent and extend an ambient air sampling network.
The EPA has given CVO until Tuesday to respond to the draft notices.
In a statement, Cadia’s acting general manager, Mick Dewar, said the company took seriously the concerns raised by members of the community.
“Nothing is more important than people’s health and safety, and we remain firmly committed to making sure that we meet all of our statutory obligations and do it in a way that is aligned with our values,” Mr Dewar said.
He said the mine had already started a human health risk assessment, a drinking water sampling program, a lead testing program and 12-month dust fingerprinting program through the Australian Nuclear Science and Technology Organisation.
Mr Reynolds said he was previously assured by CVO that there was no dust pollution.
“The constant comment back was, ‘It’s water vapour, Bruce,'” he said.
The Reynolds family’s blood tests showed high levels of the heavy metal selenium.
“I am so worried about the future for my daughter and for all the children around here,” Ms Reynolds said.
“All the families — you’ve got babies, you’ve got pregnant women.
“We can’t stop breathing — we know it’s landing on our roof, because it’s in the air.”
The ABC has seen blood test results from several other residents who live near CVO.
The most common elevated heavy metals are selenium and nickel.
Jann Harries, whose property is one of the closest to CVO, says the community’s relationship with the mine has deteriorated in recent years because of the dust.
“[You can] taste, smell and see the dust,” she said.
“It comes over the valley — you can see it coming across the hill behind us.
“Windows are open and we get a dust cover on the benches.
Lead has also been found in Ms Harries’s water tank and her blood tests showed elevated levels of selenium.
She is still waiting for more results from additional tests.
“Currently I’m OK, I feel OK,” Ms Harries said.
“Yes, I’ve got some lead and some selenium, but I feel that I’m not at risk at this point of time.”
Community-led rainwater testing near Orange finds one in three tanks have unsafe lead levels
NSW Health is retesting water after residents raised concerns about elevated traces of heavy metals, which they worry is linked to Cadia goldmine
More than a third of the water samples taken from rainwater tanks near Orange as part of a citizen survey and tested by an independent laboratory showed lead results above the safe levels in the Australian drinking water guidelines.
Those results are now being re-tested by New South Wales Health in an effort to determine if there is a broader public health risk. NSW Health has not provided any updates about those test results or said whether they confirm the results of the initial testing.
Seventy-one samples from regional properties in central western NSW were analysed in a Sydney laboratory over summer after a number of residents raised concerns about the safety of their household water supplies. Twenty-seven indicated lead levels above the national guidelines.
The concerns were first flagged in response to dust clouds at the Newcrest Cadia goldmine. All samples are from properties located within 15km of the mine which do not have access to town water.
The sampling program was coordinated by the Cadia Community Sustainability Network (CCSN) with the support of Dr Ian Wright, a University of Western Sydney researcher, as part of a community science study into the impacts of the mine on water quality.
In a statement to Guardian Australia, a spokesperson for CCSN said they received results in February that “showed some rainwater tanks seemed to have accumulated heavy metal in the bottom of the tank”.
They then sent the initial samples plus a few more to a different laboratory to be tested again.
“This scoping exercise confirmed the preliminary results,” the statement said. “In total we have now tested 40 residents in the district.
“We have provided the information to the Environmental Protection Agency and NSW Health. NSW Health is planning to retest the pilot study to determine next steps.”
Wright told Guardian Australia the source of the contamination had not been confirmed, but that the lead levels were such that he recommended they seek further testing.
“The results are just gobsmacking,” he said. “There are children drinking this stuff.”
One sample showed lead levels that were 84 times the safe level of 0.01mg/L in the Australian drinking water guidelines.
Two of the samples contained traces of arsenic. A number also contained high levels of copper and zinc, but not above the drinking water guidelines.
Wright said the source of the contamination was a secondary concern.
“The primary question is a human health question,” he said. “Should there be a public health warning issued? Should people be drinking this water?”
Some of the initial 71 samples were of water collected from farm shed roofs, Wright said. Cross-contamination from farming chemicals and machinery had not been ruled out.
NSW Health last week confirmed it had been contacted by residents who were concerned about their water supply and environmental health officers had begun collecting samples of rainwater that serves as private household water supplies, which will be tested at government-approved laboratories.
But it stressed it does not have a role in investigating where the contaminants may have come from, and that management of private water supplies – which includes household rainwater tanks – was the responsibility of the property holder.
Because the results concern private water sources, they will not be released unless a broad public health risk is identified.
The Environmental Protection Agency (EPA) also confirmed it had received a complaint but said it did not comment on ongoing investigations.
Newcrest is also conducting sampling and sending water to be tested at ALS Laboratories, which are providing results directly back to both residents and the mining company.
“Some residents have started receiving their test results directly from the independent experts undertaking the testing,” a spokesperson said. “Tests show drinking water is safe for those who have received their results so far. We are still waiting for the remaining results and analysis of the large scale testing program to come through over the next couple of weeks.”
Earlier, Newcrest said allegations of dust contamination from the mine did not match its own monitoring and stressed that the cause was “currently unknown”.
CCSN said it was hoping to undertake isotope testing of the heavy metals found in the samples, which may help narrow down its origin.
“The CCSN isn’t attributing blame for this contamination until it can be clearly identified where the source has come from,” the spokesperson said. “We hope that NSW Health and the EPA will quickly determine some clear next steps for the community.”
Wright said it was possible that old water pipes and tanks could be the source of some of the metals seen in the samples, particularly copper and zinc. Lead has not been used in water pipes in Australian homes since the 1930s and the use of a lead-based solder on drinking water pipes has been banned since 1989.
NSW Health to test for heavy metal contamination in private rainwater tanks near regional goldmine