A review of the use of environmental offset as a policy mechanism in the environmental impact assessment process (EIA) in Western Australia

This paper reviews the use of offsets in the Western Australian (WA) environmental impact assessment (EIA) process. First, an overview and analysis of offsets as a policy tool in EIA is provided, noting that it has its origins in the practice of ecological restoration and uses the principle of the no net loss (NNL). Second, the implementation of WA offset policy is discussed noting the emergence of two new types of offsets in response to the uncertainty associated with some major resource projects. The first type is a ‘residual risk’ offset, which is provided in recognition of the uncertain risks associated with the proposal. The second type is a ‘banked’ offset, which is called upon only in the event that negative environmental impacts occur. Finally, it is proposed that these ‘offsets for uncertainty’ could be used more broadly in EIA where there is significant uncertainty of impacts provided the residual risk is considered acceptable.