Australian research key to contamination clean-up

Posted 27 June 2016

contamination clean-upAir Force bases around Australia have been coming under fire from communities amid fears of toxic groundwater contamination but Australian research may hold the key to remediating affected areas. 

Carcinogenic chemicals – perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) – have been detected in groundwater extracted near RAAF bases: Williamstown in New South Wales, Oakey in Queensland, and communities north of Adelaide.

While used in common household products, such as Teflon, Scotchgard and Gore-Tex clothing, the chemicals have been linked with a range of illnesses in human beings and animals, depending on the level of exposure.

Based out of the University of Newcastle, the CRC for Contamination Assessment and Remediation of the Environment (CRC Care) has developed a technology to remediate fire-fighting chemical contamination of wastewater and soil.

“Remediating is really all about mediating risks caused by contaminants,” CRC Care Managing Director Ravi Naidu said.

“We have been able to remediate wastewater and contaminated soils. Our technology locks the toxic substances. Once they are locked, the risk the toxins pose is reduced.”

Ravi said the technology works in a similar fashion to adding lime to farming soils to bind excess bioaccumulation of cadmium from fertilisation.

“The material we developed – matCARE – does exactly the same thing. It locks toxic substances, such that they do not leach and are not taken up by plants,” Naidu said.

“If someone ingests the soil, it won’t be leached into the human gut, either. So you can safely leave these remediating materials in the soil without any worries at all.”

While the full extent of the contamination in Williamtown, Oakey and north Adelaide is not yet known, Ravi said the magnitude of contamination depends solely on where PFOS/PFOA compounds have been received.

“The potential for risk is associated with what or who the receptors are,” he said.

“Groundwater is not static, it is moving, so the receptor could be a riverine system, or any aquatic system. Your receptor could also be anyone using vegetables grown using contaminated water.”

Meanwhile, in Williamtown, a $3.5 million project has been launched to connect 165 homes and businesses inside the investigation area with town water supplied by Hunter Water.

“Hunter Water has fast-tracked the 12km water main project to provide town water to those people living inside the investigation area, having been told this is a project of significance to the NSW Government,” said Hunter Water Interim CEO Jeremy Bath.
“I hope having access to town water residents sourced from Hunter Water’s network will provide some much-needed relief.”

The utility is also testing water storages to ensure that contamination hasn’t reached non-groundwater supplies, including Grahamstown Dam.

“Hunter Water publishes monthly the results of independent laboratory testing of its water sources, demonstrating that its water is free of PFOS/PFOA contamination,” Bath said.

While the connection project is being delivered in stages, due for completion by July 2017, Hunter Water has been involved in community awareness initiatives since mid-2015.

In February, the utility suspended the Australian Oil Refineries’ licence to discharge trade waste into sewer systems after PFOS/PFOA compounds were detected in wastewater at a rate of 116ug/L of PFOS and 1.14ug/L of PFOA.

Hunter Water’s Jeremy Bath said bans on commercial fishing due to potential PFOS/PFOA toxicity, as well as general business interruption, has caused financial hardship for communities.

“The financial impact posed by the fishing bans in Tilligerry Creek and Fullerton Cove for local commercial fisherman can’t be overstated. People who have been working on these waters for generations have in the blink of an eye had their livelihood put on hold,” Bath said.

“Drive to Port Stephens and it’s clear that visitor numbers have dropped. Whether it be running a dog kennel, the local golf club or a bed and breakfast, activity has all but dried up. “

The Australian Department of Defence is undertaking a long-term environmental investigation and assessment of groundwater beneath the Oakey site, and surrounding areas, while water supply to businesses and parks in Adelaide’s northern suburbs have been cut during EPA assessment.