Acceptable post-closure performance of decommissioned mining operations is a critical factor in persuading today's environmentally conscious public that the mining industry will not continue to burden future generations with the legacy of environmental tragedies. Post-closure impacts must be identified and managed through robust engineering design if the post-closure environment is to be environmentally sustainable. To manage potential post-closure risks (environmental, health, safety, social and economic) within acceptable limits, WMC incorporates a risk-based approach to closure planning and engineering design. WMC's risk-based closure engineering design process provides a simple methodology for developing robust closure plans - the process engineers out' unacceptable risks and engineers in' a sustainable post-closure environment. Benefits of the risk-based process include stakeholder endorsed closure criteria for an agreed post-closure land-use, focusing of resources on major risks, and a realistic and accurate estimate of the required closure provision. The outcome is an increased likelihood of satisfying the three pillar goals of sustainable development - a financially sound solution that poses a low risk to the environment and future generations.