Abstract:
INDICATOR DEFINITION
The environmental impacts and risk of contaminated sites in the Australian Antarctic Territory and Australian sub-Antarctic Islands.
TYPE OF INDICATOR
There are three types of indicators used for State of the Environment reporting:
1. Describes the CONDITION of important elements of a system;
2. Show the extent of major PRESSURE exerted on a system;
3. Determine the RESPONSE
... to either condition or changes in condition of a system.
This indicator is one of: CONDITION
RATIONALE FOR INDICATOR SELECTION
Contaminated sites remediation must be carefully prioritised to ensure it is directed towards the sites creating the greatest environmental risk because of the high cost of site remediation and the quantities of contaminated material involved. Environmental risk assessment is a crucial stage of this prioritisation process.
This indicator will measure change over time in the environmental impact and risk posed by contaminated sites in the Australian Antarctic Territory and Australian sub-Antarctic islands. The overall environmental impacts and risk should decrease as the high risk sites are remediated.
DESIGN AND STRATEGY FOR INDICATOR MONITORING PROGRAM
Monitoring
Spatial scale: Geographic coverage is Latitude (-70 to -53) Longitude (+60 to +160).
Frequency: Data downloaded directly from the Australian Antarctic Division Contaminated Sites Register. Yearly up-date on 30 June.
Measurement technique: Sites are sampled and analysed to characterise contamination and are surveyed to estimate volumes. Information on each site is collated in the Contaminated Sites Register and selected fields from the register are reproduced in the SIMR.
The primary data for this indicator is held on the Australian Antarctic Division's Contaminated Sites Register. The register stores information on areas known to be, or strongly suspected of being, contaminated. Data on each site has been obtained from site survey, published literature and a series of unpublished reports. It is updated when new information becomes available on previously contaminated sites or when additional sites are contaminated.
Environmental risks of contaminated sites are assessed against a standard set of criteria and assessments are collated in the Australian Antarctic Division Contaminated Sites Register. Data from selected fields from the register are downloaded directly to SIMR.
Assessment of environmental risk: environmental risk will depend on the types of contaminants present, the physical characteristics of the site (such as topography, presence of water etc) and the environmental values that could be impacted by the site (such as fauna and flora, scientific sites etc). Considered together, these are used to determine the likelihood and consequences of environmental impact. A matrix of likelihood and consequences is used to arrive at a rating for environmental risk.
During sites assessment, contamination is classified as one of the following,
-Highly hazardous to human health (includes asbestos, caustic soda and acid)
-Polychlorinated bi-phenols (PCBs)
-Mixed wet (may include petroleum hydrocarbons and heavy metals such as in an abandoned waste disposal site)
-Contained petroleum hydrocarbons (such as fuel in drums or bladders)
-Petroleum hydrocarbon contaminated sediments
-Heavy-metal contaminated sediments (includes metaloids such as arsenic)
-Biological (includes introduced species)
-Heritage items
-Recyclable materials
-Other
More than one type of contamination may be at a site. The categories listed above are hierarchical with the most hazardous contamination at the top. The site is classified according to the highest category of contaminant present.
The physical characteristics of the site are classified as one of the following,
-Highly unstable site, contaminants very likely to be mobile
-Moderately unstable site, contaminants may be mobilised
-Stable site, contaminants unlikely to be mobile.
Sites may create risk to a number of environmental values. Sites are classified in the Contaminated Sites Register according to the highest category of environmental risk associated with them.
The following process was used to arrive at a rating of environmental risk
1. Environmental risk was assessed for each of the following environmental aspects that could be impacted by the site,
-Human health
-Fauna and flora
-Natural physical or chemical phenomena of air, water, snow/ice, soils, rocks
-Scientific value
-Historic value
-Aesthetic or wilderness value
2. For each environmental aspect, the spatial and temporal scales of potential environmental impacts were estimated and these were combined to derive a rating for the consequences of environmental impact.
Spatial Temporal
. Long-term / Intermediate / Short-term
. greater than 10 years / 1-10 years / less than 1 year
Widespread
greater than 1km2 / Extreme / Very high / Medium
Intermediate
100m2-1km2 / Very high / Medium / Low
Local
less than 100m2 / Medium / Low / Negligible
3. The likelihood of each potential environmental impact was estimated. The estimates of likelihood and consequence were combined to derive an estimate of environmental risk for each potential environmental impact (the words at different positions in the matrix below describe the environmental risk).
LikelihoodConsequences
. Extreme / Very high / Medium / Low / Negligible
Almost certain / severe / severe / high / major / significant
Likely / severe high / major / significant / moderate
Moderate / high / major / significant / moderate / low
Unlikely / major / significant / moderate/ low / very low
Rare / significant / moderate / low / very low / very low
4. If more than one type of impact is possible for any given category of environmental aspect, repeat steps 2 and 3.
For example, if it is almost certain that there are local, short term effects on fauna and flora the environmental risk would be rated as significant; if it is also possible (moderate likelihood) that there are impacts that are long-term and of intermediate spatial scale the environmental risk would also be rated as major.
5. This process treats all the categories of environmental aspects as being of equal concern. They can be ranked if required.
The default classification for sites that have not been investigated is,
-Environmental Risk - Unknown
After Environmental Risk Assessment sites will be classified as either,
-Environmental Risk - Severe
-Environmental Risk - High
-Environmental Risk - Major
-Environmental Risk - Significant
-Environmental Risk - Moderate
-Environmental Risk - Low
-Environmental Risk - Very low
For sites that may impact on several environmental values the environmental risk reported for that site is the highest category of risk identified.
LINKAGES TO OTHER INDICATORS
Linked to the risk assessment of contaminated sites and the remediation of contaminated sites indicators. 
