Sound chemicals ‘relatively low risk’

Toxic firefighting chemicals found in Cockburn Sound are at safe levels for recreational users, according to recent testing by Cockburn Sound Management Council as the Department of Defence moves forward with groundwater sampling in the area.

The HMAS Stirling naval base at Garden Island was caught up in a widening investigation of the long-term impact of the foams used at military bases across the country, with fears the chemicals had contaminated Cockburn Sound.

But extensive testing at 18 sites in January 2017 by the inlet’s management council revealed concentrations were below the Australian Government’s health-based recreational water- quality guidelines.

CSMC chairwoman Kateryna Longley confirmed the sampling of perfluoroalkyl and polyfluoralkyl substances, commonly know as PFAS, were at or below the limits of reporting. She said there was no evidence PFAS contamination identified by the DoD’s preliminary sampling program at HMAS Stirling had impacted water quality in Cockburn Sound

The results come as the DoD plans to sink bores near the naval base and surrounding areas to examine how far PFAS chemicals had leached into ground water.

Speaking at a community briefing session in Rockingham last week, Australian Navy Rear Admiral Clinton Thomas said the bore testing was part of a thorough investigation across Australia and there was no cause for concern. “We don’t believe there are any widespread community concerns at the moment … and we do consider this site is relatively low risk because it’s an island,” he said.

“Rather than taking samples from existing bores, we’ll sink our own bores.

“We’ll follow detections down to the trace level and then we’ll know how far it extends.

“Where the initial detections have been found, people don’t drink bore water from those locations.

“We’ll keep everyone updated regularly and that’s part of our commitment to the community of being open and transparent.”

Bore testing will be conducted by independent contractor RPS Environmental and is due to progress over the next 12 months.

The department said residents were welcome to contact the PFAS national hotline on 1800 365 414 to discuss eligibility for water assistance.