Current activities
One of the current priorities in the Human Impacts stream is research in support of clean-up and remediation of contaminated sites in Antarctica, including the development of site specific environmental guidelines. Contaminated sites in Antarctica were generated as a consequence of past activities such as waste disposal and accidental spills. Now all waste is either incinerated or returned to Australia for disposal, but we still have a number of abandoned waste disposal sites that we need to clean up and, unfortunately, despite all our precautions to prevent them, accidental spills do still occur occasionally.
The total quantity of contaminated material in the whole of Antarctica has been estimated at 1 to 10 million m3. Although this is not a lot in comparison with other regions of the world, most of it is concentrated in the small ice-free coastal areas where most research stations are built and which are also used by Antarctica's unique fauna.
Our research is providing Australia with the capability to fulfil its environmental obligations by remediating contaminated sites in Antarctica. We are developing new remediation technologies, and providing the scientific basis for environmental targets and environmental monitoring, to ensure clean-up results in significant environmental improvements.
Our research at Casey has shown that some contaminated sites in Antarctica are having environmental impacts. Assessment of the likely environmental impacts is being used as the basis for establishing priorities for clean-up. Not surprisingly, the climate is the main problem with contaminated site clean-up in Antarctica. When the ground is frozen it is very difficult to excavate. But when it melts, the large amounts of water that flow during the brief summer thaw create new problems with the dispersion of contaminants.
We have developed and tested novel water treatment systems specially designed for separating contaminants from water in cold and remote places. In addition, a freeze-thaw facility is being used to test materials for use in remediation in cold climates. We are also investigating and refining in situ bioremediation technologies, which use soil microbes to break down contaminants. Our research shows that small additions of water or nutrients in the form of fertilisers significantly increase the rates of in situ break-down by the natural microbial communities.
As it will never be possible to remove all traces of contamination from Antarctica, we need targets for remediation to indicate when contamination has been reduced to the point that it no longer poses an ecological risk. In the warmer parts of the world environmental targets and guidelines are based on an understanding of the levels of contaminants that cause toxic effects in local animals and plants (ecotoxicology). Our research is providing some of the first sensitivity data for Antarctic species and will be used to determine whether environmental guidelines based on temperate regions are sufficient to protect the Antarctic ecosystem.
Finally, we have designed environmental monitoring to ensure that removal of the contaminated material does not cause additional environmental disturbance, for example by dispersing contaminants more widely.
