Argyle landscape

Closure

We recognise our impact and responsibility do not end when our operations cease, so we consider closure in the way we design, build and run every site.

We seek to create a consensus with stakeholders on a shared vision for the land, balancing environmental and community considerations with long-term capital implications associated with water treatment, repurposing and/or remediating land. Our goal is to leave a positive legacy, delivering value for the Group and our stakeholders.

Our approach to supporting regional economic development includes a strong focus on economic diversification. We endeavour to foster wider economic activities alongside national and local governments and community development plans. We provide career support and training opportunities to help the local workforce – including our own – transition to new opportunities as operations wind down. And we work with local Indigenous groups to ensure areas are looked after for future generations – right down to the kind of plants we use to regenerate land. This reflects our commitment to sustainability as well as our aim to have communities thrive long after our operations close.

Accordingly, we look for commercial opportunities to repurpose assets to reduce the social and economic impact of closure. At a number of our former assets, we are exploring options to repurpose the site for renewable energy, such as our pilot photovoltaic cells at Marignac, France, a former ferro alloy plant. At times we partner with universities and other companies to find opportunities to repurpose and reprocess waste and improve water and waste treatment. For example, in the Saguenay – Lac-Saint-Jean region of Quebec, Canada, we worked with local blueberry growers to create a safe and effective fertiliser made from waste created by our aluminium operations, anhydrite.

Over the next five years we will transition a number of assets into closure and to their next use.

  • Argyle Diamond Mine
  • Diavik Diamond Mine
  • ERA
  • Gove Bauxite Mine

Argyle Diamond Mine

Following the last production from the Argyle mine in 2020, we anticipate that it will take five years to decommission and dismantle the mine and undertake rehabilitation, followed by a further period of time for monitoring.

Argyle continues to employ people post-mining to work on rehabilitation and monitoring, continuing to pay wages and contributing to the local economy. We target 14% of our closure budget to be spent with Traditional Owners and local providers.

Diavik Diamond Mine

We are also committed to safely and responsibly closing our Diavik Diamond Mine in Canada and have planned for its closure from the outset. We will cease production at Diavik in 2025, at which time there will no diamonds left to economically mine. We are currently undertaking detailed closure planning studies that cover not only site reclamation but also employees, communities and business transition planning.

ERA

At Energy Resources of Australia’s (ERA) Ranger Mine in the Northern Territory, uranium mining and processing has now ended. Progressive closure of the mine is continuing; Pit 1 has been filled and is currently being revegetated and Pit 3 is being filled.

ERA’s Ranger Mine Closure Plan outlines the path for progressive rehabilitation, which began in 1995. ERA is tracking towards 2026 for the completion of closure work.

The mine is owned by Energy Resources of Australia (ERA), which is 86.3% owned by Rio Tinto. The Ranger Mine Closure Plan (MCP) is updated and submitted for ministerial approval annually. The MCP was developed, and continues to be updated, in consultation with regulators, scientific advisors and key stakeholders including the Gundjeihmi Aboriginal Corporation and the Northern Land Council, as representatives of the Mirarr Traditional Owners, and Northern Territory and Commonwealth Government agencies. Since 2012, ERA has spent more than A$642 million on rehabilitation and water management, to incorporate the Ranger mine into the surrounding Kakadu National Park.

Gove Bauxite Mine

While mining continues at our Gove bauxite operations, also in the Northern Territory, we have begun progressive closure activities, including the decommissioning and demolition of the refinery. We are also planning for the next stage of closure by doing things like upgrading the water treatment plant. We expect our mining operations at Gove to cease in 2030.

2020 performance

Our work supporting operating assets has expanded and between 2018-20, we completed 14 asset closure strategies, covering 35% of our assets. These create a progressive vision for future land use after our operations cease and help ensure closure is considered throughout the asset lifecycle.

All of our operating assets have tactical closure plans in place, aligned with our closure framework. We regularly review and update these plans to ensure they reflect stakeholder expectations and seek to improve our closure practices as we learn from them. At operations with joint ownership structures, we work in partnership with other asset owners to embed closure into asset design, planning and operations.

Over the next five years, we will transition a number of assets into closure and to their next use.

We continue to engage stakeholders of our sites nearing closure – including Indigenous Peoples, government, employees and host communities – via engagements and partnerships, which in turn helps them plan their future. For example, collaboration with the local community and regulators at Mount Rosser, Jamaica, led to successful revegetation of this former bauxite mine, a legacy site, which now supports local employment and is also home to an increasing number of wildlife.

Our Argyle Diamond Mine, in Western Australia, ceased production in 2020 after nearly 40 years of operation. Following closure, the land will be returned to the Traditional Owners as the custodians of Country, for activities such as cattle grazing, tourism, cultural use and possibly small-scale agriculture and native food production. We also have a target of 14% of our closure budget to be spent with Traditional Owners and local providers.

We are also supporting our Argyle employees’ transition to new career opportunities, either within Rio Tinto or externally, based on their personal goals and preferences. We began a structured career coaching programme in 2017 to ensure people were well prepared for the mine’s closure, which included providing formal training – of their choice – to all employees. To date, we have found new roles for 90% of Argyle employees who wanted to be redeployed within our company.

The Ranger uranium mine, operated by ERA, in the Northern Territory, Australia, ceased production in early 2021. Progressive closure of the mine is continuing; Pit 1 has been filled and is currently being revegetated and Pit 3 is being filled. ERA is tracking toward 2026 for the completion of closure work.

While mining continues at our Gove bauxite operations, also in the Northern Territory, we have begun progressive closure activities, including the decommissioning and demolition of the refinery. We are also planning for the next stage of closure by doing things like upgrading the water treatment plant. We expect our mining operations at Gove to cease in 2030.

We have 92 active legacy assets around the world. At the end of 2020, closure provisions on our balance sheet totalled 13.3 billion (compared with $11.1 billion in 2019). For more detail on our financial liabilities related to closure, please refer to the Rio Tinto Annual Report 2020.

 

Small animal perched on rock

Legacy sites

We also manage a number of historic sites – known as legacy sites – that we did not operate, but for which we are now responsible through acquisitions and mergers. We rehabilitate these sites and, where and when we can, transfer them to local authorities or third parties. In situations where we can not relinquish the site, we make sure it is in a safe and stable condition, and the cost of aftercare is appropriately provided.

As a member of the International Council of Mining & Metals, we contributed to the development of the ICMM Integrated Mine Closure Good Practice Guide. We are also actively participating in two of the 2019-21 Closure Working Group projects – External Reporting Metrics and Key Performance Indicators.

Two Sumatran rhinos

Saving the Sumatran Rhino

Turning an old gold mine into a Rhino sanctuary
In 2017, our historic gold mine in Indonesia, Kelian, was assessed by the government and the World Wildlife Fund as an ideal location for the highly endangered Sumatran rhino. Part of the site has now been designated a Protection Forest and will be used as a sanctuary for housing and breeding rhino, with the aim of eventually releasing them into the wild.

More

Our Kelian team rehabilitated the 6,670-hectare gold mine site, including remediating waste dumps and building dams to protect ground and surface water from mine tailings, and converting areas that lay beneath the processing plant into a wetland.


It’s hoped the sanctuary could provide the lifeline that Kalimantan’s remaining Sumatran rhinos need to begin their recovery – and is just one example of the contribution that thoughtful closure of former mine sites can make.