Technical reports

Case Study: National protocols for assessing site contamination

Case Study:

National protocols for assessing site contamination

22 August 2013

      • Work by CRC CARE is behind a major overhaul of national standards for assessing and managing contaminated sites
      • The new National Environment Protection Measure is now complete and available to industry and regulators

      Ensuring national harmonisation

      Australia’s National Environment Protection Council (NEPC) has legal responsibility for setting national standards in seven areas of environmental protection, including air quality, used packaging and contaminated sites. The NEPC’s ‘measures’ – developed for all of its areas of responsibility and known as National Environment Protection Measures, or ‘NEPMs’ – facilitate consistency across jurisdictions and ensure that the best quality information is available for regulators and managers.

       Although its first recommendations on contaminated sites appeared in 1999, rapid advances in the science of site assessment and treatment, and in knowledge of potential health impacts, led to a decision in 2005 to revise them.

      Following extensive input from CRC CARE, CSIRO, the National Health and Medical Research Council and other scientific and industry partners, and with subsequent reviews and administrative steps completed, the new National Environment Protection (Assessment of Site Contamination) Measure was officially adopted in May 2013.

      Informing a stronger NEPM

      In revising this NEPM, CRC CARE provided information and advice in the following areas:

      • petroleum hydrocarbon fractions and related analytical methods
      • characterisation of sites contaminated with petroleum hydrocarbons
      • field assessment and biodegradation of petroleum hydrocarbon vapours
      • health screening levels for total petroleum hydrocarbons
      • contaminant bioavailability and bioaccessibility
      • community consultation.

      Particular advances developed by CRC CARE included new recommendations on how different levels of hydrocarbon contamination in soil should trigger different management responses in order to protect human health. Known as ‘health screening levels’ (or HSLs), they represent the most advanced consensus available on the health risk of soils contaminated by hydrocarbons. They also differentiate between different depths for soil, soil vapour and groundwater, and between sand, clay and silt.

      International influence

      Collaboration between Australian and Canadian authorities during the revision also resulted in the Canadians recommending that Australian levels of protection, as well as the Australian ‘species sensitivity distribution’ (SSD) method be adopted for their own use. SSDs are models of the variation in sensitivity of species to a particular stressor (e.g. some sort of contaminant).

      In April 2013 the governing body of NEPC, the Australian Standing Council on Environment and Water, endorsed the revised NEPM as ‘the premier document for the assessment of site contamination in Australia, used by regulators, site assessors, consultants, environmental auditors, landowners, developers and industry’.

      Much of CRC CARE’s work towards the new NEPM is available via its Technical Report series, which may be downloaded as PDF files.

      Also see the feature on CRC CARE’s policy work published by AusIndustry, the division of the Australian Department of Industry that administers the CRC Program.  

Threats to people and wildlife

PFAS can be dangerous to human health. In particular PFOS (perfluorooctanesulfonate) and PFOA (perfluorooctanoic acid) are two commonly used PFAS that are known to enter ecosystems and move up food chains, accumulating in animal and human tissue, including the liver and blood. PFAS have been linked to bladder and liver cancer, endocrine disruption, and developmental and reproductive toxicity, including neonatal mortality,1 and are potentially lethal to animals.

Are there safe levels of PFAS?

The Stockholm Convention on Persistent Organic Pollutants has listed PFAS as chemicals of concern to human health.2 PFOS is listed under Annex B (restriction) of the Convention and PFOA was proposed for listing in 2016. In 2016 the US EPA issued new, more stringent drinking water health advisory levels of 0.07 parts per billion (ppb) for both PFOS and PFOA.3 PFAS-contaminated animal food chains in the US have had PFOS levels as high as 59,500 ppb.4

PFOS and PFOA in the environment

PFOS and PFOA are increasingly being phased out of modern foams. Concentrations in human blood appear to be decreasing in the US, although they are still rising in China.5 Today they remain significant residual contaminants at many sites globally, for example, at many of the world’s 49,000 airports (including 450 civilian and military airports in Australia).

Foams are also deployed on fires at traffic, truck and railway accidents and even building fires. As at airports, the chemicals can escape into the surrounding urban or rural environment and contaminate water supplies.

Analysing with confidence

Australia does not yet have the infrastructure to ensure the quality and comparability (across different laboratories) of PFOS/PFOA measurements. To address this gap, two CRC CARE Participants – the National Measurement Institute and Environment Protection Authority Victoria – are collaborating in a CRC CARE-funded project to develop and demonstrate PFOS/PFOA ‘proficiency testing’, which assesses the performance of different labs and analytical methods by comparing their results for a single sample. Participation in proficiency tests helps provide end-user confidence in overall data quality and the reliability of results. The project will support Australian environmental policy and improve PFOS/PFOA analysis in Australia. For more information about the project please contact Cheryl Lim (cheryl.lim@measurement.gov.au).

Cleaning up with clay

Aware of the high adsorption properties of clay-based materials, scientists at CRC CARE identified one clay type that was especially effective in trapping the contaminant PFAS. By tailoring its mineral constituents, researchers were able to fine-tune the clay’s adsorption properties to achieve full recovery of the PFAS.

In further laboratory trials this modified clay, named matCARETM, remediated both water and soil, removing PFOS, PFOA and other fluorinated surfactants to below detection limits.

Defence against AFFFs

Based on this research, CRC CARE has established remediation facilities at Royal Australian Air Force sites in Edinburgh (SA), Pearce (WA) and Townsville (Qld), where years of foam use, mainly in fire-fighter training, had caused substantial PFAS contamination. Treatment has so far resulted in the clean up of over 1 million litres of water to less than the reporting level of 5 ppb.

To further improve the clean up of PFAS, CRC CARE has developed an anionic surfactant test kit (astkCARE™), which can be used to detect AFFFs.

As research reveals more about the long-term effects of PFAS on people and animals, it is likely that governments and communities will demand increasing restrictions on their use, as well as lower levels of environmental contamination. This new technology from CRC CARE is ready to play a key role in the response.

Get in touch

For more information and to discuss how CRC CARE can help you assess and remediate AFFF-contaminated soil and wastewater, visit our website or contact Adam Barclay at adam.barclay@crccare.com or on +61 429 779 228.

References

  1. Betts, KS (2007). ‘Perfluoroalkyl acids: what is the evidence telling us?’, Environmental Health Perspectives vol. 115, iss. 5, pp. A250-256.
  2. Stockholm Convention (2009). Governments unite to step-up reduction on global DDT reliance and add nine new chemicals under international treaty. United Nations Framework Convention on Climate Change COP4.
  3. USEPA (2016). PFOA & PFOS Drinking Water Health Advisories. USEPA Fact Sheet.
  4. Oliver-Verbel, J, Tao, L, Johnson-Restrepo, B, Guette-Fernandez, J, Baldiris-Avila, R, Byrne-Hoyos, I & Kannan, K (2006). ‘Perfluorooctane sulfonate and related fluorochemicals in biological samples from the north coast of Colombia’, Environmental Pollution vol. 142, issue 2, pp. 367– 372.
  5. Renner, R (2008). ‘PFOS phase out pays off’, Environmental Science and Technology vol. 14, issue 13, p. 4618.