Publications

Acknowledgments

The National Strategy for the Management of Scheduled Waste, endorsed in 1993 by the Australian and New Zealand Environment and Conservation Council, requires that the PCB management plan:

1. is based on a risk assessment of environmental and human health effects, and the social and economic impacts;
2. specifies threshold concentrations, threshold quantities and notifiable quantities of chemicals;
3. indicates dates for cessation of the generation of scheduled waste, for cessation of the use of articles containing scheduled waste, and the disposal of scheduled waste; and
4. takes into consideration the principles defined in the Intergovernmental Agreement on the Environment (IGAE).

While meeting the last three objectives, the National Advisory Body and the Scheduled Wastes Management Group found it not possible to obtain a risk assessment of the environmental and human health impacts and to address possible synergistic effects of PCBs and other substances in setting management provisions contained in this plan.

Risk assessment methods for chemicals can be applied to situations where human beings or the environment are exposed to those chemicals. The risk can be estimated from a combination of the inherent hazard of the chemical (the toxicity) and the likelihood of exposure to that chemical. For pesticides, it is possible to estimate risk from the inherent hazard, which is based on the toxicity to animals, and likely exposure to the pesticide. In combination with safety factors, the inherent hazard is then used to generate what is known as an Acceptable Daily Intake (ADI). These values are then used in setting regulatory measures for pesticides.

It is difficult to apply this approach to industrial chemicals in containers or equipment, such as is the case for PCBs. The lack of exposure data relating to the intentional release of PCBs in the environment makes it particularly difficult to estimate risk to the non-human environment. Thus, the National Advisory Body and the Scheduled Wastes Management Group did not find it possible to apply a formal risk assessment method to situations in which PCBs are found because of the numerous possible scenarios involving PCBs and the limited information on the synergistic effects of PCBs or on how to use this information in setting management provisions.

ADI values have not been used as a basis for the provisions in this plan. It has not been possible to link particular values for ADI to expected levels of exposure through, for example, disposal of non-scheduled PCB waste to landfill and then to develop specific management provisions. Likewise, while data on the bioaccumulation and bioconcentration of PCBs and the acute, sub-acute and chronic effects of PCBs on animals have been considered, it has not been possible to use the data as the dominant basis for developing the management plan. A relative risk management methodology was therefore adopted, where PCBs posing a higher risk to human health or the environment, due to their concentration or location, are to be subject to more stringent requirements, including priority for phase out from use.

In addition to this plan, those involved in PCB management must comply with relevant statutory instruments to meet their full obligations.

However, in some instances, it is possible to assess the risk likely to arise from particular PCB treatment facilities and where this is the case, assessment is required by this management plan (see Section 9.5.1).

This plan does not address issues relating to contaminated soils that are dealt with by the Australian and New Zealand Guidelines for the Assessment and Management of Contaminated Sites. However, storage, transport, treatment and disposal of scheduled and non-scheduled PCB contaminated soil are subject to the provisions of this plan.

The plan will be subject to periodic review. Any new information or risk assessment methods which may have an impact on the management provisions in the plan, particularly information on human health effects and environmental toxicology of PCBs, will be examined as part of this review.

Finally, it is important to recognise that this management plan will be given effect through Commonwealth, State and Territory statutory instruments and, as such, it represents guidance to governments.

Professor Ian Rae
Chair, National Advisory Body and Scheduled Wastes Management Group