When is it time to say enough is enough for historical mine rehabilitation and closure? A Pilbara case study

摘要

Mine rehabilitation and closure standards, and stakeholder expectations regarding these, have changed significantly over time. In particular, over the last 20 years, regulator, community and industry expectations on what constitutes acceptable rehabilitation and walk-away solutions have increased dramatically. This has improved rehabilitation and closure outcomes, but this has also raised the bar to an often unrealistic level for historical mine sites. It can increase closure costs, prolong (or even prevent) site relinquishment and damage stakeholder confidence in a company's and the broader industry's ability to undertake mining in a sustainable manner. Is it fair to expect a historical site to meet modern standards or are these expectations setting up operations and companies to fail? The imposition of current or future closure standards on older operations is a major concern for industry. There is a need for a new approach and dialogue regarding the actual environmental and community risks associated with historical sites, and what rehabilitation and closure standards are practical and should apply. If there are no sensitive receptors and the risks have been contained or are being managed effectively, why go any further? This does not mean that mine operators should ignore their responsibilities and that new mines should not be expected to achieve higher standards or best practice, but decisions need to be made on the most practical, pragmatic and cost-effective way to utilise what are often limited resources in rehabilitating and closing historical mines. To adopt a new approach, it is important that stakeholders understand the standards that were applied when mining at a site commenced and/or when a mine was operational, and what closure outcomes are realistic. Perhaps there are alternative, and possibly better, environmental outcomes that can be achieved rather than trying to achieve the impossible on a site that was not set up to current-day standards? This paper discusses the Blue Spec Shear Gold-Antimony Project near Nullagine, Western Australia, and draws on other examples, to trigger a conversation within industry, regulators and the community about whether historical sites can meet modern rehabilitation and closure standards, and if a new site relinquishment approach is required.