Collapses in commodity prices or demand, cost spirals or changes in government can all trigger a company to abandon their mine, with taxpayers left to pick up the bill for what’s left: ugly, dangerous or even toxic.
Holding companies to account is a growing problem in Australia; the committee held public hearings across six states and visited numerous sites, including two in the Pilbara, in an effort to find answers.Committee chairwoman, Victorian Greens Senator Janet Rice, wrote that this was “disappointing”.
The Australian Greens made 32 recommendations, amounting to a significant boost to Commonwealth involvement. They wanted a complete inventory of mine sites, more research funding, enforceable targets, legal changes and establishment of a national oversight body. Tasmanian Liberal Senator Jonathon Duniam made no specific recommendation but wrote that the primary responsibility rested with the states. He said any nationwide proposals that placed retrospective or additional obligations on companies could jeopardise the “continued operation of Australia’s resources sector” and put existing projects at risk.How you rehab a mine
In this context, the term includes designing and constructing landforms and establishing sustainable ecosystems, depending on the use aimed for. This includes reconstructing a soil ‘profile’, choosing species, establishing plants and introducing animals.The term rehab needn’t mean you create a similar ecosystem to the one before; for example, it might mean replacing a woodland with a plantation or grazing land.
The term ‘restoration’ is used for an attempt at re-establishing something like the original ecosystem.WA’s ARC Centre for Mine Restoration told the committee government instructions were often vague and simplistic, leaving widespread industry confusion.
The science on best practice is still emerging as a specialty field (spearheaded in WA by the ARC Centre) and the ARC Centre commented that the industry was not sufficiently equipped to provide real restoration.The committee saw firsthand some of the difficulties companies face in the complex project of rehab when visiting BHP’s Pilbara northern tenements including Yarrie mine, closed in 2014 and still being rehabilitated, and the former mining town of Shay Gap, closed in 1994, now considered fully rehabilitated.
‘No major mine sites relinquished in WA’
The Australia Institute told the inquiry that “seemingly simple questions are very difficult to answer”; that most state governments did not have or did not publish simple data on how many mines were operating, how many abandoned, how many closed, how many suspended.The best data available for WA is from 2012 and suggests there were 9870 abandoned mines.
“Relinquishments of mine sites that are fully rehabilitated and suitable for alternative further use are extremely rare. No examples or statistics could be found of relinquishment of major mine sites in the big mining states of Western Australia or Queensland,” it submitted.No definitive national costings were available but the committee heard evidence the cost of rehabilitating all major abandoned mine sites in Australia would run into the billions.
Western Australia used to have a bond system but now has a financial assurance scheme based primarily on a pooled rehabilitation fund, with QLD following suit.The first is Ellendale Diamond Mine in the Kimberley region, abandoned in 2015, now managed by the state while it undertakes an Expression of Interest process for a new operator.
Corporate responsibility (or lack thereof)
The first was the practice of mines being placed indefinitely into ‘care and maintenance’, where the site is maintained and infrastructure remains intact until production recommences or the mine is closed.
The second concern was larger mining companies selling mines to smaller operators towards the end of the mine life, with significant rehabilitation liabilities outstanding, another possible strategy to avoid rehabilitation obligations.
This was a particular risk where the costs of rehabilitation had been significantly underestimated; in these instances, requirements that the new operator must have sufficient funds to meet any rehabilitation liabilities were meaningless, one submission said.‘Voids to the horizon’
Professor Kingsley Dixon, head of the ARC Centre, giving evidence to the inquiry in Perth, described coal pits in Collie as “voids to the horizon” and said “backfilling” such pits was, at this stage, beyond current technical ability.
The inquiry discussed at length whether, and when, companies should be allowed to leave pit voids and waste rock dumps as an accepted part of ‘rehab’ plans. The Australian Conservation Foundation submitted that a conscious decision to allow open pits and voids to remain post-mining was “extremely contentious”, and argued that in such cases it was a decision by regulators that explicitly favoured corporate interest over that of the community and environment.Professor David Mulligan of the Centre for Mined Land Rehabilitation at the University of QLD commented that the discussion had largely been around the strip mines of the coal industry.
“While we possibly needed to accept the unlikelihood of voluntary backfilling where another viable, safe and economic use for the void can be identified and proven, there would seem to be limited arguments … to allow approvals for new coal mines, for example, to plan to leave a final void,” he said. Committee members heard when they travelled to Rio Tinto’s active Yandicoogina iron ore mine in the Pilbara that so much earth was taken from the pits that it was not possible to backfill them.
Rehabilitation was planned to involve creating the deepest pit lakes possible with the smallest possible surface area to limit surface evaporation of water.
BHP told the inquiry that depending on the environmental impact, the company might decide to partially backfill its voids in the Pilbara northern tenements to a level above the water table, if the water was of poor quality.The federal government has no obligation to provide a response to the report, and it is as yet unclear whether it will.
Find out how mine rehabilitation legislation in Australia is changing in our FREE guide.
Useful links:
- Speak to our team for a free demo of our mine rehab (rehabilitation) tool DecipherGreen
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