What On Earth Is Under Us?
A decade-long investigation by mapping and spatial intelligence experts raises red flags over more than 260,000 sites that could be toxic hotspots ...
WITH Australia’s long history of mining, agriculture and manufacturing, our wide brown land has been affected by soil, water and air contamination since the arrival of the First Fleet.
From polluting gas works to leaching landfills; toxic industrial plants to unregulated dry cleaners; and leaking petrol stations to cancer-causing PFAS chemicals in our waterways – the impacts of the country’s contamination history run deep.
“We are dealing with a legacy of an industrial past and this is becoming an increasing issue as our towns and cities grow,” says risk-mapping expert Howard Waldron, co-founder of award-winning spatial intelligence firm Lotsearch.
“The land available for development can be subject to a potential issue or hazard – whether it’s in a flood zone, fire zone or if it’s a contamination hotspot.
“And, if it’s a contamination hotspot, the contamination isn’t necessarily restricted to a particular site, it could be migrating through the soil, or surface and groundwater to other sites close by.”
The first prominent cases of soil contamination in Australia came to light in the 1970s with a timber treatment plant causing multiple pollution incidents in Armidale, NSW. In the 1980s elevated lead levels were found in the bloodstreams of children living near South Australia’s Port Pirie lead smelter.
Around the same time, in Queensland and NSW, cattle tick dip sites were of concern due to elevated DDT and arsenic detected in the soil.
In the 90s, industrial sites in cities were earmarked for residential redevelopment and a clearer picture emerged of the extent of countrywide contamination as audits on industrial land identified thousands of contaminated sites.
Today, around the country, new contamination sites continue to surface. Last month, Water NSW took the precautionary measure of disconnecting Medlow Dam in Sydney’s Blue Mountains from the water supply when PFAS chemicals were found in levels exceeding the Australian guidelines. Further contamination was found in water samples from other nearby sites, not considered to be PFAS hotspots, leading Water NSW to presume the chemicals – which can travel far in creeks and waterways – may have migrated from elsewhere.
As community concerns about these ‘forever chemicals’ grows, the Federal Government has announced a wide-ranging national inquiry into PFAS, chaired by Victorian senator Lidia Thorpe, who describes PFAS as “the asbestos of the 21st century”.
“We’ve already seen worrying instances of cancer clusters with suspected links to PFAS chemicals,” says Thorpe. “We cannot take them seriously enough.”
Most state-based Environmental Protection Authorities, now maintain and update land registers and lists of priority sites which are deemed contaminated, or are potentially contaminated and under investigation.
However, Howard Waldron says: “What governments know about and publish on registers are still very few sites in comparison to what the actual potential is, which should be of concern for conveyancers and property lawyers when advising their clients.
“Because sites have to go through a rigorous testing and investigation phase, a vast number of sites we have identified have not been tested and therefore remain potential sites of contamination” says Waldron, whose team at Lotsearch has uncovered 260,000 potentially affected sites across the country. “We identify, through historical data, where those contaminating activities have been taking place so that people can then do further investigations if they need to.”
While remediation of affected land can be costly and take considerable time, developing and living on land once it’s cleared of contamination is becoming increasingly common.
Just ask the 12,000-strong population residing on Sydney’s Rhodes Peninsula – previously the toxic birthplace of the country’s chemical industry and home of Union Carbide – which was successfully remediated in 2011. The NSW EPA continues to monitor the site and residents are advised to use raised garden beds and imported soil if they want to grow vegetables.
Likewise, expensive harbourside land in Hunter’s Hill on the Old Radium Hill processing plant site was remediated and last month (August) deemed safe for residential redevelopment, 100 years after the initial contamination which included nuclear waste.
“Environmental consultants, engineers and auditors, take a risk-based approach when remediating sites. In some cases, land can be re-used for residential purposes, but there may need to be on-going monitoring and management of the site.” says Waldron. “Potential purchasers will want to be made aware of the previous uses of a site, the remediation action plan and any ongoing obligations”.
