Where required, Defence conducts preliminary investigations to review the historical use and storage of legacy firefighting foams at Defence sites. The findings of preliminary investigations are used to determine if further, more detailed, environmental investigations into PFAS are necessary. Current and past Preliminary Site Investigations are listed below. Click on an investigation for further information.
Salt Ash Air Weapons Range - Ongoing
The Department of Defence has completed a Preliminary Site Investigation (PSI) on the Salt Ash Air Weapons Range, as part of a national environmental program to investigate and manage the presence of per- and poly- fluoroalkyl substances (PFAS), across the Defence estate.
The PSI involved a review of potential historical use, storage and disposal of legacy firefighting foam at the Range and included sampling of groundwater, surface water, soil and sediment. Sampling was primarily undertaken on the Range, with limited sampling undertaken in the surrounding area.
PFAS was only found in low concentrations and no exposure risks were identified. Based on the findings of the PSI, no further environmental investigations are required.
The full PSI report is available below as well as a Conceptual Site Mode, Sampling and Analysis Quality Plan and a factsheet that summarise the findings.
For further information contact the information line on 1800 714 139 or SaltAsh.Defence@aecom.com, or view the factsheet below.
Preliminary Site Investigation Report
Salt Ash residents within the existing EPA PFAS Management Area
In November 2017, the NSW Environmental Protection Authority (EPA) designated a Management Area, as part of the nearby RAAF Base Williamtown Environmental Investigation. This Management Area is approximately 400 metres south-west of the Salt Ash Air Weapons Range.
Salt Ash residents within this Management Area should continue to follow the EPA’s precautionary advice, as part of minimising exposure to PFAS, originating from the RAAF Base Williamtown. For more information contact 131 555 or visit www.epa.nsw.gov.au
RAAF Base Scherger - Complete
In January 2018, Defence finalised a Preliminary Site Investigation into per- and poly-fluoroalkyl substances (PFAS) at RAAF Base Scherger. Based on the findings of this report, it has been determined that there is currently no requirement for further environmental investigations into PFAS at and surrounding the Base.
The Preliminary Site Investigation involved the review of historical use, storage, and disposal of legacy firefighting foam and included sampling of soil, sediment, surface water, and groundwater, to identify where and when the foam was used, stored, and disposed (sources), and associated PFAS contamination at the property.
Key findings of the Preliminary Site Investigation:
- Sampling of soil, surface water, sediment and groundwater on base found PFAS was not widespread and only found in low concentrations.
- PFAS was not detected in the RAAF Base Scherger drinking water.
- Surface water from the base flows into Mission River, to the north and west of the base, through a drainage network and tributaries. The highest concentration of perfluorooctane sulfonic acid plus perfluorohexane sulfonic acid (PFOS+PFHxS) found in surface water on the base was below the drinking water guidelines.
- Previous investigations showed groundwater flowing in a west to north-west direction towards Mission River. The highest concentration of PFOS+PFHxS found in groundwater between the base and Mission River was below the drinking water guidelines.
The full Preliminary Site Investigation report is available below: