Seven potentially deadly pollutants

TWO centuries of industrial development has left a legacy of toxic risk for millions of households, mapping and spatial intelligence analysts from Lotsearch have discovered.

GASWORKS

Beginning in the late 1800s, gasworks were built to produce town gas for heating, lighting and cooking with extensive sites located in the heart of our growing cities like Sydney’s Barangaroo, the South Melbourne Gasworks and the Newstead Gasworks in Brisbane.

In NSW, the state’s EPA says the operation of over 60 former gasworks sites throughout the state has left a legacy of soil and groundwater contamination which should be addressed before the land is reused.

“Some of these contaminants are carcinogenic to humans and toxic to aquatic ecosystems and so may pose a risk to human health and the environment,” says the NSW EPA. “As a result, many former gasworks sites will require remediation before they will be suitable for sensitive land uses, such as housing.”

The NSW Department of Environment and Conservation says gasworks were typically located “near waterways or train lines for easy delivery of coal. They were often also close to the centre of the city”.

In Melbourne, the former Fitzroy Gasworks – just 2km from the CBD – was known as one of the city’s most contaminated sites. But, after four years of rehabilitation, completed in 2022, the land is now slated for development of 1,200 apartments.

The Barangaroo site in Sydney also proved “challenging” for the developers of the Crown Casino and surrounding skyscrapers, according to the NSW EPA.

Remediation work has been necessary at many gasworks

It “involved cleaning out a large area and taking major steps to contain very smelly odours from tar as it was dug up and carted out to minimise the impacts on neighbours, including residents. It also involved the removal of an old tar tank and gasholders, below a major road in a busy area.

“This remediation has provided useful lessons and trial findings which will be used to regulate future remediation sites”.

“The EPA has lifted the contaminated land declaration and Infrastructure NSW completed the remediation ahead of schedule”, enabling Barangaroo to become a thriving precinct with commercial office space and recreational areas.

SERVICE STATIONS

Crisscrossing the nation, underground petroleum storage systems (UPSS) are one of the most common sources of both land and groundwater contamination in Australia – and pose a real danger of contaminating neighbouring land.

According to the WA Department of Water, service stations can pose contamination risks to water resources through the “leakage of fuel, and the spillage of engine coolant, hydraulic fluid, lubricants and solvents, along with the inappropriate containment or disposal of wastes such as car parts, batteries and tyres”.

The Victorian EPA says: “UPSS have the potential to leak, leading to expensive cleanup costs, damage to the environment and risks to human health.” 

In NSW, with more than 7,000 historic sites and around 2,500 modern sites (Lotsearch data), leaks from underground fuel tanks and pipework at service stations are a common source of soil and groundwater contamination, according to the EPA.

“Service stations make up the single largest sector of contaminated sites in NSW,” says the state’s environmental agency, “and proper assessment of service station sites is crucial to making sure human health and the environment are protected from potential impacts of contamination.

“Of the many thousands of decommissioned service station sites in NSW, there may be some with elevated concentrations of petroleum product in soil and groundwater.”

Using old telephone books to map the locations of historic service stations, Lotsearch has identified more than 22,000 sites where service stations once operated countrywide, along with nearly 7,000 modern sites.

For the owners of affected neighbouring properties, financial compensation can be difficult to come by. In August this year, David Harris, the member for Wyong in NSW, called on the owners of a Kanwal service station, which was declared “significantly contaminated” by the EPA in 2018, to shut down until petrol storage tanks contaminating the site and nearby properties were fixed. 

Harris said a cleanup order, issued by the NSW EPA in 2020, had been ignored by the service station owner’s Zoya Investments P/L, and more than 3,000 litres of petrol could have leaked from the underground storage tanks and into adjacent properties. 

One neighbouring property owner is owed $8.45million in damages from the service station proprietors, who, according to Harris, declared no assets in April 2024 “to avoid responsibility to clean up the petrol station site”.

DRY CLEANERS  

Prior to 1991 dry cleaners in Australia were unregulated with many historical sites left unchecked and capable of leaching toxic solvents, like Perchloroethylene (PERC) and Trichloroethene (TCE), into surrounding soil and waterways.

Linked to increased cancer risks, PERC can also lead to air pollution through volatile organic compounds (VOC) emissions. While exposure to the potentially carcinogenic TCE can happen through air, water, or skin contact, and can affect a person’s central nervous system. 

In 2016 the Department of Veterans’ Affairs formally recognised exposure to TCE as a cause of Navy veteran Keith Bailey’s Parkinson’s disease. Mr Bailey had been exposed to the chemical for up to 12 hours a day in his job cleaning motor parts onboard Navy ships. 

Across the country, Lotsearch has identified around 5000 sites which have the potential to be affected by historical dry cleaner activities and could pose a risk to health and land values. 

US-based company EnviroForensics says PERC is one of the more expensive contaminants to remedy. And the cleanup of a contaminated dry cleaning site is often more complicated than a cleanup of a contaminated petrol station because petroleum products will float on water while PERC is heavier than water and will sink down past groundwater tables until it hits bedrock. 

Dry-cleaning historically used toxic chemicals such as PERC

“When a release of PERC to the ground occurs and it reaches down to the groundwater table, it will continue to sink until it hits a layer of dense material, like clay,” says the environmental consultancy group. “It will sit there and continue to dissolve for a long time, which can cause a long groundwater contamination plume.”

According to SA Health, when these long-lasting chemicals like PERC and TCE contaminate soil and water supplies, they can spread far from the original source of contamination and be difficult to remediate. 

“In some cases contaminated groundwater and soil vapour can move off industrial sites and may be present under residential properties,” the government department states.

This was the case in 2003 in Brunswick, Victoria, when buyers of 49 recently completed units, located next door to a former Spotless dry cleaners, could not move into their apartments after the EPA discovered soil contamination. The developer was unaware the site was contaminated and had to cancel the sales and pay the construction costs of the building, forcing them into administration. In 2007, a judge ordered Spotless to pay $7million for remediation of the site.

LANDFILL 

Historic landfill sites – going way back to the First Fleet – were often located in quarries and gullies with little engineering and no lining to prevent leaching of contaminants into the soil and groundwater. 

According to the NSW Environmental Protection Authority, landfills have the potential to produce a number of pollution streams including leachate, stormwater runoff, landfill gas, offensive odour, dust, noise and litter. 

“These pollutants can degrade the quality of surrounding surface water bodies, groundwater, soil and air,” says the environmental agency. “Landfilling activities have the potential to adversely affect local amenity, and they may also affect threatened species of flora and fauna, native vegetation and items of Aboriginal heritage.”

In their Sydney University research paper, A History of Solid Waste Management in Sydney, authors Ranasinghe, Withford, & Withnall say the historic haulage of waste was expensive and so the “numerous bays and inlets of Port Jackson, Parramatta River, Cooks River and Georges River are dotted with parks and reserves which were all once disposal sites. Similarly, many of Sydney’s sporting fields were once waste dumps.”

Lotsearch research shows that, in Victoria alone, there are over 750 unique current and historical landfill sites, comprising over 35,000 lots.

Victorian environment and planning law firm Kellehers Australia says that “old landfills pose a significant danger to the use and development of land. This danger is not restricted to the land on the landfill itself. Neighbouring land can also be at risk of contamination.

“Landowners need to be cautious when using land that could be near an old tip. It can be difficult to even know their location. Some were never lined and pose a considerable risk of off-site contamination. The management of these landfills also raises difficult challenges for current owners, operators and authorities.

“Buffers are needed because of the potential for “gas migration”, a process by which gases escape and rise through the soil. Gas migration can lead to the contamination of nearby land with dangerous or explosive vapours.”

The South Australian EPA says landfill gas is generated by decomposing material in landfills and includes methane. 

“If not properly controlled, the gas can travel underground and present an explosive and asphyxiation hazard at neighbouring properties,” says the authority. “The extent of the risk depends on the size and age of the landfill, the type of waste deposited there, the presence of water, and geological conditions.”

GROUNDWATER

Contaminated groundwater can pose significant risks to human health and to our ecological systems and is an expensive and tricky problem to manage and remediate.

Often the legacy of human activities, including leaking industrial storage tanks, manufacturing discharge, agricultural runoff and improper waste disposal, groundwater contaminants can include pesticides and toxic chemicals and metals. 

According to Geoscience Australia, groundwater – the water below the land’s surface – makes up approximately 17 per cent of our accessible water resources and accounts for over 30 per cent of our total water consumption.

“Groundwater is a major source of water for many urban and rural communities as well as industry and agriculture,” says the Bureau of Meteorology. “In some places it is the only water available. Groundwater also sustains many rivers and wetlands during dry periods.”

In Australia, groundwater contamination sites of note include areas across Adelaide affecting Edwardstown, Clovelly Park and Glenelg East; the Albion Explosives factory site in the Melbourne suburb of Cairnlea; and The Botany Sand Beds Aquifer that extends north from Botany Bay to Surry Hills and Centennial Park in Sydney. 

In South Australia, environmental mapping company Lotsearch has identified over 30,000 lots impacted by groundwater contamination while, in Victoria, the company has pinpointed over 17,000 lots of concern.

The Victorian Department of Health says: “Some groundwater supplies in Victoria have been found to contain high levels of chemical contaminants, such as arsenic, which can cause illness in people who drink the water.”

And the Victorian EPA concedes the problem of groundwater contamination is not easily resolved. “Once contaminated, groundwater is very difficult to clean up and usually becomes a long-term environmental legacy,” warns the agency.

SURFACE WATER

As Australia’s metropolitan centres grow and spread, our rivers and waterways are under increasing pressure from urbanisation and the legacy of past industry and other polluting land use.

A research paper for the Australian Parliament by Bill McCormick from the Department of Science, Technology, Environment and Resources says, “Australia’s climate and landscape, coupled with the demands of agriculture and a growing urban population, can make water supply a difficult matter”. 

“In terms of rainfall, Australia is the driest inhabited continent, and the amount of rainwater that enters rivers is also very low. On average, only 12% of rainfall flows into rivers in Australia…in addition, our rainfall is often highly variable: ‘droughts and flooding rains’ is an apt description of the natural condition in much of the continent.

“The growth of urban centres puts pressure on existing water supplies both directly (more homes) and indirectly (more food consumption and industrial use).”

Contaminants from industrial and agricultural runoff; disease-causing microorganisms from humans, livestock and other animals; bushfires and floods which introduce chemicals and debris into waterways; plastics and other rubbish; algal blooms; and PFAS chemicals all play their parts in surface water contamination. With heavy metals like arsenic, cadmium and lead, often introduced to rivers and other waterways through industrial processes and corroded plumbing.

“Our water resources are of major environmental, social and economic value… and when water is polluted the value of the resource can be reduced,” says the NSW EPA. 

“Water pollution can be caused by both point source (such as industrial and treated sewage discharges) and diffuse sources (such as stormwater runoff from agriculture and urban areas).”

In the past, NSW has experienced a number of surface water contamination scares including fish consumption warnings in the Shoalhaven River and the secret dumping of 100,000 tonnes of toxic waste, including asbestos, on an illegal dumping site near Wheeny Creek in the Hawkesbury region.

Chemicals found in surface water can cause health problems like cardiovascular disease, cancer and gut health issues. 

“Contamination can become a risk to human health when…there are ways the contamination can reach people,” says the VIC EPA. “Contamination from land can make its way into groundwater, rivers and creeks. People may use these waterways for drinking water and irrigation, or for recreational activities. For example, fishing and swimming.”

PFAS

Known as ‘forever chemicals’ PFAS have been in the news for all the wrong reasons in recent months with the detection of elevated concentrations of these potentially toxic substances found in Sydney’s water catchments.

The Medlow Dam in the Blue Mountains, which provides water to 41,000 residents, was closed as a ‘precautionary measure’ after tests last month (August) revealed elevated levels of PFOA, one of the forever chemicals. 

Described as the ‘next asbestos’ PFAS – a group of nearly 4,700 synthetic chemicals – have been used in a variety of products including non-stick cookware, Scotchgard, fire-fighting foam, sunscreens, fitness wear and cosmetics. They are bio-accumulative, which means they accumulate over time in living organisms including humans. 

In Australia, historical use of fire-fighting foam has resulted in increased levels of PFAS being found at sites including defence bases and airports. And, in May 2023, the Commonwealth settled a $132.7 million class action over PFAS contamination affecting 30,000 residents across seven sites around Australia, located close to defence bases. 

Forever Chemicals closed Medlow Dam in Sydney’s Blue Mountains earlier in 2024.

Lotsearch has mapped the PFAS investigation areas related to these defence sites and airports, affecting over 45,000 lots, and includes this information in their reports. 

According to the Australian Government PFAS Taskforce, the properties that make some PFAS chemicals useful in many industrial applications and particularly in fire-fighting foams, are the same properties which make them problematic in the environment. 

“The PFAS of greatest concern are highly mobile in water, which means they travel long distances from their source-point; they do not fully break down naturally in the environment; and they are toxic to a range of animals,” says the taskforce. 

“While understanding about the human health effects of long-term PFAS exposure is still developing, there is global concern about the persistence and mobility of these chemicals in the environment. 

“Many countries have discontinued, or are progressively phasing out, their use. The Australian Government has worked since 2002 to reduce the use of certain PFAS.”

Environmental group Friends of the Earth says the Australian Government needs to do more to protect citizens.

“PFAS chemicals have been linked to a number of diseases,” says the group, “yet the Australian Government stubbornly refuses to end the use of PFAS chemicals in Australia, even after they have been banned overseas.”