Four decades of imposed uranium mining by Energy Resources of Australia (ERA) and Rio Tinto is about to end at the Ranger uranium mine in Kakadu in Australia's Northern Territory.
What remains is a heavily impacted site that requires extensive, complex and costly rehabilitation. This must meet both community expectation and the mining company's legal obligation to restore the site to a standard where it can be incorporated into the surrounding Kakadu World Heritage area.
As mineral processing winds down at Ranger ahead of a mandated 2021 end to operations, a new report has found that Kakadu, Australia's largest national park, is at long-term risk unless the clean-up is comprehensive and effective.
Unfinished Business, co-authored by the Sydney Environment Institute (SEI) at the University of Sydney and national environment group the Australian Conservation Foundation (ACF), examines the ERA Mine Closure Plan which outlines the rehabilitation works.
The report identifies significant data deficiencies, a lack of clarity around regulatory and governance frameworks and uncertainty over the adequacy of current and future financing – especially in relation to future monitoring and mitigation works for the mine site.
Mine operator ERA and parent company Rio Tinto are required to clean up the site to a standard suitable for inclusion in the surrounding Kakadu National Park, dual-listed on UNESCO's World Heritage list.
No mine in the world has ever successfully achieved this standard of clean-up and the rehabilitation project is attracting national and international attention. This interest has put increased pressure on the Australian and Northern Territory governments, and on ERA and Rio Tinto, to get this work right.
The outcome at Ranger is of critical importance to Rio Tinto's international reputation as a responsible corporate citizen and the company's wider social license to operate. The report argues that Rio Tinto's future access is directly linked to its efforts to repair past impacts.
Concerns over the adequacy of the rehabilitation plans and the financial capacity needed to deliver a comprehensive clean-up operation have been formally raised with Rio Tinto at the company's annual meetings in both London (April) and Perth (May).
Ranger has been one of the most contested and high-profile resource projects in Australia since the mine was opened in 1981 despite the clear opposition of the Mirarr Traditional Owners and other Aboriginal people of the Kakadu region.
The challenge now facing Rio Tinto is not to simply scrape rocks into holes and plant trees, it is to make sure mine tailings, radioactive slurry and toxic by-products of mining are isolated from the surrounding environment for 10,000 years.
"Achieving this in a monsoonal environment like Kakadu raises enormous environmental and governance challenges," said report co-author Dr Rebecca Lawrence from the Sydney Environment Institute. "For the rehabilitation process to even have a chance at success, the existing opaque and complex regulatory regime needs an urgent overhaul".
Tailings ‒ the waste material remaining after the processing of finely ground ore ‒ are one of the serious environmental risks at Ranger. The report examines how ERA and Rio Tinto intend to deliver on the federal government's requirement to protect the Kakadu environment by isolating any tailings and making sure contaminants do not result in any detrimental environmental impacts for at least 10,000 years.
Long after the miners have gone, this waste remains a direct human and environmental challenge. This issue is key to the long-term health of Kakadu, but there is insufficient evidence and detail on how this work will be managed and assured in the future. Without this detail there will be a sleeping toxic time bomb deep inside Kakadu. This work is a key test of the commitment and capacity of Northern Territory and Commonwealth regulators as well as the mining companies.
At its recent twin AGMs, Rio Tinto again committed to make sure ERA has the financial resources to deliver its rehabilitation obligations, but the financial mechanism to do so remains undisclosed and uncertainty persists.
The report makes recommendations to improve the chances of a successful clean-up at Ranger. It calls for increased transparency and community input, the public release of key project documents, a better alignment of research and operations and open review processes for key decision points.
Australia has a long history of sub-standard mine closure and rehabilitation in the uranium and wider mining sector, and there is a clear need for a better approach and outcome at Ranger. The challenge is how to rehabilitate the heavily impacted mine and larger Ranger Project Area in a way that reduces adverse impacts and provides confidence that the living and peopled landscape of Kakadu is best protected, now and into the future.
The full report ‒ Unfinished business: Rehabilitating the Ranger uranium mine ‒ is online at https://www.acf.org.au/unfinished_business_rehabilitating_ranger