RAAF Base Tindal

Latest updates

​Important information for communities around RAAF Base Tindal.

July 2023 - April 2024 Ongoing Monitoring Report (PDF, 36.77 MB)

July 2023 – April 2024 Ongoing Monitoring Report Factsheet (PDF, 1.16 MB)

Community information session Factsheet – October 2024 (PDF, 1.01 MB)

Community information session Posters – October 2024.pdf (PDF, 5.03 MB)

Community information session Presentation – October 2024 (PDF, 4.95 MB)

Investigations and findings

In November 2018, Defence completed investigations into per- and poly-fluoroalkyl substances (PFAS) contamination on and around RAAF Base Tindal.

PFAS contamination from RAAF Base Tindal is a significant issue for the local community. Defence is committed to working with the Northern Territory (NT) Government to manage, remediate and monitor PFAS contamination in the area.

The investigations found that PFAS are mostly concentrated in areas where firefighting foams were previously used, stored or disposed. These are called source areas. PFAS in these locations can be found in soil and in water flowing through the source areas. PFAS moves in surface water flowing through drains and creeks or groundwater that flows underground through soil and rock.

Two source areas were identified on the base where PFAS was found in soil or groundwater at concentrations that required further assessment or action:

• Fire training area
• Fire station area

Human Health and Ecological Risk Assessment

As part of the investigations, Defence conducted a Human Health Risk Assessment and Ecological Risk Assessment. This assessment measured the PFAS exposure risks to people living, working and undertaking recreational activities within the management area and to local plant and animal life.

This assessment found that drinking bore water presents an elevated exposure risk at properties where PFAS was detected above drinking water guidelines. These properties have been contacted and are being supplied with alternative drinking water.

More detail on Defence’s risk assessments can be found in the Human Health Risk Assessment factsheet and the Ecological Risk Assessment factsheet.

To support communities reduce their exposure to PFAS, the NT Government has issued precautionary advice for the consumption of some bushfoods in the Katherine area. For more information, please refer to the Northern Territory Department of Health’s Bushfoods in Katherine fact sheet (PDF 103.4 KB)

The NT Government also provided advice for eating fish, shellfish and crustaceans from Katherine River (between Donkey Camp Weir and Daly River) and Tindal Creek Please refer to the Northern Territory Department of Health’s Fishing in the Katherine area fact sheet (PDF 202.8 KB).

Additional investigations

Defence has investigated how and where PFAS are moving from source areas and how much PFAS are leaving the base. These studies helped determine the best remediation actions to reduce the amount of PFAS leaving RAAF Base Tindal.

At RAAF Base Tindal, PFAS were found to be primarily moving through groundwater. Surface water discharges to Tindal Creek also contributes to some of the PFAS moving off the base. To prevent PFAS moving from the source areas, Defence is treating contaminated soil and operates groundwater treatment plants to reduce PFAS in groundwater. 

Remediation and management

The aim of remediation is to minimise PFAS leaving the base by focusing on the remediation and management of source areas. The main source areas at RAAF Base Tindal are the fire training area and fire station area.

Over time this remediation will reduce the amount of PFAS in the management area. Defence has a PFAS Management Area Plan setting out the proposed remedial works and other management actions to manage potential risks presented by PFAS.

Most remediation actions recommended in the PFAS Management Area Plan for RAAF Base Tindal are complete. Defence anticipates final remediation works will be completed in the coming months.  

Fire training area and fire station area

Investigations confirmed that the fire training area and fire station area are the largest sources of PFAS leaving the base. 

Both of these source areas have been remediated using a process called soil stabilisation. Soil stabilisation involves digging the contaminated soil out of the source area and treating it with activated carbon to bind the PFAS. This reduces its ability to wash out into stormwater and groundwater. The treated soil is then placed back to the area and covered with a clean layer of topsoil and grass to prevent erosion and minimise exposure to rainwater.

Groundwater remediation 

Since 2019, Defence has operated two groundwater treatment plants on RAAF Base Tindal to remove PFAS from groundwater and to reduce the amount of PFAS moving off base. These plants have treated over 3 billion litres of PFAS contaminated groundwater to date. 

Managing Katherine’s impacted water supply

PFAS contaminated groundwater has impacted the groundwater used for drinking water in the Katherine area. To address this, Defence works with the NT Power and Water Corporation to treat PFAS impacted water before it enters the town water supply.

To secure a long-term water supply for Katherine, Defence funded the construction of a permanent groundwater treatment plant in Katherine. The permanent plant can treat up to 10 million litres of water per day and replaces a temporary water treatment plant that Defence provided in 2017 to remove PFAS from Katherine’s water supply. The plant is funded by Defence, with Power and Water Corporation operating the plant since May 2024.

In areas where residents rely on bore water that has been impacted by PFAS, Defence is providing residents with an alternative water supply or rain water tanks.

Further information about drinking water in the Northern Territory, including the Katherine Water Treatment Plant, can be found on the Northern Territory Power and Water website.  

Reports from the management of Water Treatment Plants are available below.

Water Treatment Plant Sampling Results Katherine Power and Water Corporation (PDF, 2.62 MB)

Water Treatment Plant Sampling Results RAAF Base Tindal Fire Training Area (PDF, 1.47 MB)

Water Treatment Plant Sampling Results RAAF Base Tindal Fire Station Area (PDF, 1.35 MB)

Ongoing monitoring

Monitoring of PFAS continues on and around RAAF Base Tindal, including the Cossack area, through sampling of surface water, groundwater and aquatic biota. Monitoring helps Defence understand if PFAS contamination is changing over time.

The results are published in an Ongoing Monitoring Report and factsheet. Defence will inform the community if changes to the management approach are required.

Reports, presentations and factsheets

Detailed reports from the PFAS investigation and management are available for download. Appendices to these reports can be found in the document archive. To discuss these reports, contact pfas.enquiry@defence.gov.au.

• PFAS Management Area Plan Update - Jul 2019 factsheet (PDF 3.5 MB)
• PFAS Management Area Plan - Jul 2019 report (PDF 10 MB)
• Human Health Risk Assessment Findings - Jun 2018 factsheet (PDF 2MB)
• Human Health Risk Assessment - Executive Summary - Jun 2018 report (PDF 1.5 MB)
• Ecological Risk Assessment Findings - Nov 2018 factsheet (PDF 1.5 MB)
• Ecological Risk Assessment - Nov 2018 report (PDF 7.6 MB)

Document archive

The RAAF Base Tindal document archive contains information that Defence has published about the management of PFAS, including older community presentations, investigation reports, risk assessments and factsheets.  

Some archived information has been superseded by recent reports and factsheets.

Documents Archive - Tindal (PDF, 284.89 KB)

Last review: 13 December 2024.