Current Trends in Risk Assessment--The Australian Experience. K. J. Lloyd, Golder Associates, 35 Hume Street, Crows Nest NSW, Australia
In 1992 the Australian and New Zealand Environment and Conservation Council (ANZECC) published "Australian and New Zealand Guidelines for the Assessment and Management of Contaminated Sites." These guidelines set out the fundamental goals for protection of public health and the flexibility for future use of land in Australia and New Zealand and are generally accepted as guidelines by each state or territory of Australia and New Zealand. Australia, however, regulates the assessment and clean-up of contaminated sites by individual state approaches. Not all states have a regulatory system designed for the assessment and management of contaminated sites; Victoria, and Queensland do and South Australia, New South Wales, Northern Territory, Western Australia and Tasmania do not. These Guidelines provide limited guidance on the approach to clean-up of contaminated sites. Environmental Investigation Criteria for approximately 15 compounds included in these Guidelines were intended as a point of departure for further environmental investigation but are being used in some states as standards for remediation. In setting risk based environmental investigation criteria Australia has heretofore used the Dutch values for remediation of soils presenting problems for a scientifically defensible approach to the fate and transport of environmental contaminants in Australian soils.
In defining it's approach to risk assessment Australia combines the US, Dutch and English approaches to the assessment and management of contaminated sites. These Guidelines provide limited guidance for the use of exposure and toxicity values, non-carcinogenic and carcinogenic risk limits, and risk management strategies. For example, ANZECC prefers toxicity values based on WHO Environmental Criteria and IARC Monographs on the Evaluation of Carcinogenic Risks to Humans over the US EPA ATSDR Toxicological Profiles. The Guidelines consider the most sensitive exposure scenario as the 2-3 year old child as a resident on a site who ingests soils at the site, ingests homegrown vegetables and inhales volatile contaminants. This child weighs 13.2 kg, incidentally ingests 100 mg of soil/day, consumes 0.05L of liquid/kg body weight/day, and inhales 4 - 5 m3 air/day.
This presentation highlights the risk assessment outlook in Australia; the regulatory approach, the academics views; and what is being used by consultants.