The 5R Model: facilitating decision-making on repurposing of industrial and ancillary infrastructure

Abstract

Closure of mining landscapes is widely discussed within, and investigated by, the mining industry with increasingly innovative alternative uses found for open pits, underground workings, waste rock landforms, tailings storage facilities and water dams. When it comes to industrial and ancillary infrastructure though, many mining companies elect only to decommission and dispose of this infrastructure onsite. However, there is a growing need for efficient, effective and sustainable ways to find alternative purposes for these features, particularly in the face of increasing resource scarcity.The concept of 'adaptive re-use' is not new: it is common in the construction industry where re-use of materials and equipment is considered to be a win-win strategy, in modern communities, where recycling and even upcycling has become second nature, and in urban renewal, where there is a focus on repurposing of heritage buildings and other structures. Further, there is growing support for the 'circular economy' ethos, which favours careful management of resources and intelligent re-use of products and reconsidering the term 'market' more broadly.Many mining companies are now adopting a circular approach in selected areas of their business and while this is mainly focused on active operations, it is considered that there is an opportunity to extend this thinking to mine closure. However, identifying what materials can be 'mined' for re-use or repurposing can be challenging, partly due to obsolescence but also because of tenure restrictions, liability issues, transport costs, legal constraints and other factors. On this basis, the '5R Model' has been developed to facilitate decisionmaking in relation to the alternative uses for industrial and ancillary infrastructure associated with mining and mineral processing operations. This paper outlines the basis of the 5R Model and the way in which this classification system can be used to guide investigations and decision-making for repurposing of industrial and ancillary infrastructure, including blue-sky options. Drawing on case studies on alternative closure scenarios for mining and mineral processing infrastructure and lessons learned from 'urban mining', this paper also discusses potential pathways to achieve these uses and facilitate custodial transfer of physical assets, and ways in which this model can also assist companies meet their waste minimisation, carbon reduction and other targets during closure of their sites.