Toxic Truth: Black slag risks 'ignored'

Warwick Burgess and Barry Butler inspect slag heap at Pasminco in 1996
pic Ron Bell
Warwick Burgess and Barry Butler inspect slag heap at Pasminco in 1996 pic Ron Bell

A DECADE after Pasminco’s lead and zinc smelter closed at Boolaroo and as the land is being prepared for redevelopment, the Newcastle Herald and Macquarie University collected more than 130 soil and  dust samples from homes and public spaces in surrounding suburbs. The analysis revealed alarming levels of contamination remained, despite a government-approved Lead Abatement Scheme.

THE state government has given only $20,000 over 20 years to Lake Macquarie City Council to deal with black slag, which scientists say is a serious pollution problem that can cause significant harm to humans.

Money from state coffers has failed to flow to the problem, despite state agencies knowing about it for decades and approving the Pasminco operation that produced the smelting waste product. 

The NSW Environment Protection Authority believes slag is a low priority, but a joint Newcastle Herald and Macquarie University study found lead in slag in a ‘‘bioavailable’’ form at Tredinnick Oval, Speers Point, at an amount almost 30 times the national standards for health-based investigation levels for recreational sites.

Bioavailability means it can be absorbed into humans and threaten their health. High blood lead levels can cause sickness, brain damage and behavioural problems in children.

Retired environmental health council officer Jim Sullivan said exposed slag was in many public areas around Lake Macquarie.

Mr Sullivan said people should be informed and the EPA needed to deal with the problem.

‘‘They walked away from it and left the council to deal with it,’’ Mr Sullivan, who formerly advised a state committee on Pasminco pollution in north Lake Macquarie, said. ‘‘The EPA has the power and expertise to deal with it.’’

A council document from 2012, obtained by the Herald under freedom of information laws, revealed the council referred the black slag problem to the EPA in 1994. A decade went by, but the problem remained in the council’s hands. From 2004 to 2010, the council ‘‘advocated for the black slag legacy to be managed by the EPA,’’ the document said.

Asked how much money the state government had given the council in the last 20 years to manage the pollution problem, the council said it received a $20,000 grant in 2004. It said the EPA had ‘‘not identified black slag as a specific area of concern’’. 

This was despite Macquarie University research finding in 2003 that heavy metals in black slag could be absorbed into the body, exposing people – especially children – to health problems. The research found ‘‘lead concentrations in certain black slag-affected soils may affect human health if the slag is ingested (from hand to mouth) or dust is inhaled in quantities above safe health thresholds’’.

The council said its approach to managing black slag on public land ‘‘directly addresses this exposure pathway by applying ‘cap and contain’ procedures to ensure a barrier to human exposure to the material.’’

‘‘This barrier commonly consists of mulch, top-soil, and/or grass cover. These processes have been determined as appropriate for preventing impacts on human health,’’ it said.

EPA director of contaminated land and environmental health Craig Lamberton said health authorities had previously found that fine lead-dust fallout from the old smelter, and not slag, was the main health concern.

‘‘If we’re going to use our public money wisely, we’d be better off focusing on things that will give us the best return for protecting the community and environment, than the lower level issues,’’ he  said.

Boolaroo Neighbourhood Centre raised concerns about the slag in a 2010 letter to the NSW Department of Planning. ‘‘We fail to understand why Pasminco and its administrators Ferrier Hodgson have failed to take responsibility for providing slag to property owners as landfill,’’ it said.

Mr Lamberton said the council and residents had voluntarily used the slag in public areas and private properties. For decades black slag, considered to have good drainage properties, was delivered free-of-charge to hundreds of Hunter homes. Trucks moved millions of tonnes of the toxic waste  from the former Pasminco smelter. Much of it was spread on public parks, foreshores, playgrounds and sporting fields. 

Most people do not know the danger  exists and none of the sites, besides the smelter land, are listed on the EPA’s contaminated sites register.

Mr Lamberton said while some may like the EPA to ‘‘get Pasminco to agree to remove the 1.5 million tonnes of slag from all around the community ...  it’s not something we have any legal ability to do’’.

He said Pasminco administrator Ferrier Hodgson had refused to take responsibility for slag in areas beyond the smelter site and was prepared to defend its position in court.

‘‘We knew we wouldn’t win that because people weren’t compelled to take the slag on their land,’’ he said.

But Macquarie University Professor of Environmental Science Damian Gore said that line of argument was ‘‘just wrong’’.

‘‘A mining company with chemists and metallurgists and geologists – a bunch of experts – offered it to a bunch of residents,’’ he said. ‘‘Knowing it wasn’t safe is part of the due diligence that surely they [Pasminco] must have observed and if they didn’t know, they should have.”

Council documents show the state government rejected the council’s proposal several years ago to include slag-affected land in the Pasminco site remediation strategy.

Mr Sullivan said the EPA had put the slag problem in the ‘‘too hard basket’’. ‘‘I don’t think they wanted to deal with it because it smacked of incompetency on their behalf as the regulator for that industry,’’ he said.

‘‘The council never issued the licence for the smelter, the EPA did,’’ he said. ‘‘All the regulations for the smelter came through the state government.’’

Mr Sullivan said the council had played its part in the problem, by distributing the slag for decades.

Lake Macquarie MP, and former mayor, Greg Piper said it would be impossible to track down all of the slag deposits across the city. 

‘‘Council and the EPA have always said that it’s a management issue,’’ he said.

The Pasminco site had more than 200,000 cubic metres of black slag on it, which the EPA ordered to be removed and placed in a containment cell – along with about 800,000 cubic metres of other contaminated material from the site, documents show.

But black slag remains in the community. A council document from 2012 said it ‘‘conducted a range of research into the distribution and management of black slag across the city’’.

The  Herald asked the council for a map of slag-contaminated areas, but it did not provide one. Black slag sites are recorded on council’s contaminated land database.

Mr Lamberton said it would not have been fair to ‘‘mums and dads’’ to place remediation orders on private properties. He said the council had ‘‘done a good job of managing slag in public areas and foreshore areas where it had been used as fill’’ – a position Mr Sullivan disputed.

The council said it ‘‘takes a risk management approach’’ to managing slag on its land to ‘‘minimise the impact on community health, safety of council workers and the environment’’.

It said responsibility for black slag on other land was ‘‘the responsibility of the landowner’’.

Lake Macquarie mayor Jodie Harrison said the council had taken a proactive approach to the management of black slag to minimise the impact on community health, council workers and the environment.

‘‘In most cases, slag deposits in Lake Macquarie city present a low health risk if the slag is covered,’’ she said.

A waste product from the Cockle Creek smelter

Small black, gritty or granular material that contains lead, cadmium, arsenic and antimony

Up to 3 million tonnes distributed through Lake Macquarie and Hunter, given away for free

Used in public reserves, parks, ovals, the lake shore, paths, kerbs and roads

Used by residents to landscape backyards

Health authorities say risk of contamination is low if slag covered, but significant risk if exposed

Lead in slag can enter the human bloodstream

Elevated blood lead levels in children are linked to intellectual impairment and behavioural problems

Source: Macquarie University and public authorities

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