PFAS stands for per- and poly-fluoroalkyl substances. These are a group of chemicals that have been widely used since the 1950s in a variety of household and industrial products to enhance resistance to heat, stains, grease and water. They have also been a component of firefighting foams that are applied to liquid fuel fires.
While PFAS compounds have been used widely for decades, recent investigations have identified that they are persistent and not known to degrade in the environment and that they also accumulate in humans and animals. As a result, PFAS compounds are considered an emerging environmental contaminant.
A small number of studies have shown associations between PFAS concentration in blood and certain medical conditions but no causal links to any form of disease have been established. The Ministry of Health has advised that there is no public health issue associated with PFAS. A major review carried out by the Australian Department of Health concluded that there was “…. insufficient evidence of causation between PFAS exposure and any adverse health outcomes.” International research into the potential health effects of PFAS is continuing.
Use of firefighting foams
Firefighting foams have been integral to maintaining safety for travellers, air crews and firefighters, used internationally in the aviation and maritime environments. They have been used to quickly extinguish liquid fuel fires on airfields in emergency situations and for emergency training.
Foams used by NZDF since 2002 have not contained PFOS or PFOA above trace levels, according to advice received from our suppliers.
In a number of cases, our suppliers have also provided documentation verifying the foams meet the HSNO Firefighting Group Standard.
To verify this, NZDF commissioned testing of firefighting foams held on NZDF camps and bases for use in firefighting. Samples of firefighting foam bulk stocks from Burnham, Devonport, Linton, Ohakea, Waiouru, Woodbourne and Whenuapai camps and bases were tested. The results showed PFOS and PFOA to be below the limit of reporting. These results are therefore consistent with the advice of our suppliers.
During the PFAS investigations conducted by NZDF some old stocks of foam concentrate were discovered in segregated storage. Samples from these stocks showed high concentrations of PFOS. This is consistent with these products pre-dating 2002. NZDF is following the authorised disposal process, as outlined by the Environmental Protection Authority, to dispose of these stocks.
While NZDF’s current firefighting foams meet the HSNO Firefighting Group Standard, NZDF stopped training with firefighting foams at its air bases in 2016. Firefighting training moved to commercial fire training facilities in Taranaki and Auckland.
However, NZDF is currently not using Aqueous Film Forming Foam (AFFF) for firefighting training anywhere in New Zealand, either on NZDF bases or in commercial facilities, while long-term training options are assessed.
The Navy trains with a biodegradable ‘eco-foam’ in a contained environment at the Sea Safety Training Squadron in Devonport.
The Ministry for Environment is co-ordinating an all-of Government response to the issue of potential environmental contamination from the historical use of PFAS that. As part of this NZDF undertook testing of ground and surface water at Base Ohakea and Base Woodbourne, and at neighbouring properties, to understand the presence of PFAS in the environment. Investigations were also conducted at Base Auckland (Whenuapai) and Devonport Naval Base.
Base Ohakea and Base Woodbourne
NZDF prioritised testing for PFAS at sites where firefighter training is known to have taken place historically, and where it is known that neighbours may be sourcing drinking water from bores or wells – Base Ohakea and Base Woodbourne.
Between December 2017 and September 2018 extensive testing was conducted of groundwater and surface water on the bases, in the surrounding environment, and on neighbouring properties. Four rounds of testing were completed at Ohakea and Woodbourne. Testing of soil, sediment, fish and plants was also conducted in some locations. These results were provided to individual landowners, and a summary was provided to government agencies and regional authorities working on this issue.
Through the programme of testing a plume of PFAS was found in groundwater and surface water originating from Base Ohakea and Base Woodbourne. In most wells, PFAS in groundwater was below the applicable guidelines. However, in some locations, groundwater exceeded the interim drinking water guideline. Where this occurred, and the water was a source of drinking water, alternative drinking water supply is being provided. At Ohakea a permanent alternative drinking water supply is being constructed to service these properties in the long term.
PFAS was also found in soil, sediment, and fish (such as eels) in some locations. In one location, a stream near Woodbourne, the regional authority placed a precautionary fishing restriction on a section of the stream. This restriction was still in place in October 2021.
Landowners were offered advice from the Ministries of Health and Primary Industries (MoH and MPI) relative to the results of testing on their properties, which is confidential to them. Following the initial programme of testing, NZDF worked with the regional authorities to develop a long-term monitoring plan, including installation of dedicated monitoring wells. PFAS testing of surface water and groundwater continues to be conducted in accordance with the approved monitoring plans, and in conjunction with the regional authorities, to measure any potential changes to the concentration and distribution of PFAS in groundwater and surface water. The test results are reported to the regional authorities.
Base Auckland (Whenuapai)
NZDF has also tested the ground and surface water of a small number of properties near Whenuapai. PFAS was found at low concentrations, in three monitoring wells. Those wells are not used for any purpose, including drinking water.
PFAS was found in streams and drains bordering Whenuapai and in some of the sediment tested from the adjacent Upper Waitematā Harbour. PFAS was also found in some of the fish and snails tested from the harbour adjacent to the base. Importantly, tests were also conducted on snails collected from an estuary in a regional park north of Auckland to act as a control site. PFAS was found in aquatic snails from the regional park. Landowners were offered advice from MoH and MPI. Test results from streams and the harbour were provided to Auckland Council and the All of Government group led by the Ministry for the Environment (MfE).
Drinking water in the community comes from the town supply and is not affected.
Devonport Naval Base
NZDF also conducted testing of groundwater beneath the Sea Safety Training Squadron at Devonport Naval Base, and of sediment in the adjacent Ngataringa Bay. PFAS was found both in the groundwater and in the sediment in the bay. Drinking water in the community is sourced from Auckland city town supply and is therefore not affected.
Both fish, snails and other invertebrates were tested from Ngataringa Bay. While PFAS was found in some of the snails and crabs, it was not found in the fish. The testing results were supplied to Auckland Council and MfE as above.
NZDF continues to work with the regional authorities. Testing is conducted twice a year at Ohakea and Woodbourne and selected neighbouring properties to monitor any changes to the PFAS plumes in these locations.
The results of all testing of animals and plants was provided to the Ministry for Primary Industries (MPI). MPI says that there is no evidence or suggestion that there is a current food safety issue.
Ministry of Health advice continues to be that there is no acute health risk.
More information about PFAS and the Government’s response to this issue, including health and food safety advice, is available at MFE.