THE SHOCKING HISTORY OF MCARTHUR RIVER MINE
To learn more about the devastating history of McArthur River Mine, and efforts over many decades by Traditional Owners to stop damage caused by it, read our timeline below.
1995 – underground mining commences at McArthur River Mine (MRM).
2003 – MRM proposes to convert from an underground to an open cut operation, necessitating the diversion of the McArthur River for approximately 5km. Environmental assessment undertaken under Northern Territory and Commonwealth legislation.
Feb 2006 – then NT Environment Minister (and current NLC CEO) Marion Scrymgour recommends that the open project not proceed because it would cause unacceptable environmental impacts. MRM lodged an alternative proposal on invitation of Labor Chief Minister Clare Martin, which re-engineered the diversion channel to some extent.
Oct 2006 – NT Mines Minister Chris Natt approved open cut conversion of MRM. The security bond is set at $55.5 million dollars. The authorisation contains a requirement for an Independent Monitor to be appointed to oversee the management of the mine by publishing annual reports on its environmental performance.
Oct 2006 – Commonwealth Environment Minister approves open cut conversion of MRM.
Dec 2006 – Traditional Owners commence proceedings challenging Northern Territory and Commonwealth approvals.
April 2007 – Traditional Owners win NT Supreme Court proceedings challenging the NT Mines Minister’s approval. Clare Martin’s Labor Government passes legislation 3 days later overriding the Court’s decision by amending the McArthur River Project Agreement Ratification Act. NT Labor MLAs Malarndirri McCarthy, Karl Hampton and Alison Anderson all cross the floor. Marion Scrymgour is not in Parliament for the vote.
2008 – McArthur River diversion channel is connected to the McArthur River.
December 2008 – Traditional Owners win Federal Court proceedings (on appeal) challenging the Commonwealth Environment Minister’s approval. However, the river had already been diverted earlier that year.
February 2009 – Labor Commonwealth Environment Minister Peter Garrett approves the open cut conversion of MRM under the Environment Protection and Biodiversity Conservation Act.
August 2009 – the first Independent Monitor report (for 2008) identifies as an “extreme” risk the misclassification of waste rock as “non-acid forming” prior to placement in the waste rock dump. It identified that tailings were oxidising rapidly and producing acid, and that the assessment of tailings as non-acid forming was likely to be incorrect (p 71). Misclassification of waste rock is identified as a risk in every subsequent Independent Monitor report.
2013 – Expansion of MRM (Phase 3) approved. This saw the mine double its capacity from 2.5million tonnes of ore to 5.5million tonnes of ore per year, and double the depth of the open pit from 210 metres to 420 metres, significantly increasing the size of the waste rock dump.
2013 – MRM changed its waste rock classification system. This revealed that the proportion of potentially acid forming (PAF) rock in the waste rock dump to be 89% (rather than less than 25% previously estimated). The main risk associated with such high rates of PAF rock is acid mine drainage, which can seep into groundwater and surface water systems over millennia.
2013 – MRM’s northern waste rock dump spontaneously combusted, caused by oxygen meeting pyritic rock in its top layers, producing sulphur dioxide and smoke. This signalled a more serious and slow acting problem associated with the generation of acid mine drainage occurring within the waste rock dump, generated from the PAF rock in the waste rock dump.
June 2014 – NTEPA calls for a further environmental impact assessment for dealing with the problems associated with the high PAF rock in the waste rock dump and associated acid mine drainage.
July 2014 – elevated levels of heavy metals in fish and invertebrates round in creeks on the mine site (both tributaries of the McArthur River).
2015 – up to 400 potentially contaminated cattle from McArthur River Station (owned by the mine) were shot in 2015 after wandering onto the mine site after floods had knocked down fencing.
2015 – the Independent Monitor characterised the acid mine drainage associated with management of waste rock in the waste rock dump as the most significant environmental issue at the mine.
August 2015 – Chief Minister Adam Giles threatened to shut the mine if it did not improve its environmental practices. The security bond was $111 million in August 2015, according to FOI documents obtained in 2016. Read here. In the FOI documents, Department CEO Ron Kelly states the bond should cover 100% of the cost of closing the mine (see article).
October 2015 – Glencore agreed to significantly increase its security bond following pressure from the Northern Territory Government. The amount of the security bond was not publicly disclosed. Read here.
October 2016 – Jack Green (represented by EDO) filed legal proceedings in the Northern Territory Civil and Administrative Tribunal challenging the Northern Territory Government’s decision not to publicly release the security bond for MRM (following an FOI request).
March 2017 – MRM submitted an environmental impact statement (EIS) for what it named the “Overburden Management Project”, designed to respond for the potential for acid mine drainage to be generated from the waste rock dump, open pit, and the tailings storage facility. The OMP proposed:
that the waste rock dump be redesigned, including by increasing its height from 80m to 140m to minimise horizontal footprint as well as runoff;
to change the dump’s cover from a clay to a geosynthetic liner to reduce rainfall infiltration rates that cause acid mine drainage;
to extend mining for tailings reprocessing, whereby the tailings would be placed back into the open pit at the end of mining and the tailings dam completely rehabilitated;
post closure, to allow the open pit to progressively fill with water, with the natural McArthur River course reconnecting through the open pit;
that monitoring of the mine site in some form would be required until 3037 (some 1020 years into the future).
September 2017 – following sustained activism and legal action by Jack Green, represented by the EDO, NT Resources Minister Ken Vowles publishes security bonds for MRM (and other mines in the NT) for the first time. As at September 2017, the MRM security deposit was $476,094,542.
October 2017 – The Independent Monitor’s audit for 2016 raised a number of concerns in relation to the EIS. It also raised concerns about the calculation of the security bond, stating (at page 4-2):
Existing mine closure costs are based on a strategy that cannot be implemented. It is likely that any revised strategy will involve additional costs both in terms of construction and post-closure monitoring and maintenance. These additional costs are currently unknown and therefore are not included in the existing security bond.
August 2018 – NTEPA recommended the OMP proceed, if 30 recommendations were implemented. The NTEPA deferred any decision on final mine closure until “technologies improve and more appropriate solutions emerge”. At the time of the NTEPA report the MRM security deposit was $477,997,771 (p 84 of Assessment Report 86). The NTEPA said in relation to the security bond that the Independent Monitor:
… in its most recent report stated that the closure costs were based on a strategy that could not be implemented and would be insufficient to manage and maintain the site post-closure (IM, 2017). The cost of rehabilitating the mine site in 2018 is likely to be substantially more than the current security. Mudd (2014), for example, estimated the cost of complete backfilling alone at $800 million.
December 2018 – Independent Monitor report for 2017 rates the insufficient security bond as a “high risk”. It states that closure costs had been calculated using the 2012 closure plan, but that the OMP had developed alternative closure options and a longer period of post closure monitoring and maintenance. It states that the “current closure costs are insufficient in the event of MRM being unable to complete rehabilitation of the site” (ERIAS, 2018). Despite the requirement in MRM’s authorisation for annual reporting by the Independent Monitor, there has been no Independent Monitor report since this date.
12 June 2019 – the Commonwealth granted approval of the OMP under the Environment Protection and Biodiversity Conservation Act. A key condition of the EPBC Act approval was that the pit lake must remain hydraulically isolated from the McArthur River an its floodplain, meaning that MRM’s proposed plan to reconnect the pit lake to the river could not be undertaken.
20 August 2019 – Resources Minister Paul Kirby announced a variation of MRM’s authorisation, by imposing conditions to create a pathway for the implementation of the NTEPA’s recommendations. The authorisation set the security bond at $519,728,466. The Mining Management Plan (MMP) was also varied, but was not publicly released despite a recommendation by the NTEPA that this occur.
19 November 2020 – NT Mining Minister Nicole Manison announced her decision to approve an amended MMP and a varied authorisation. Part of the MMP and the varied authorisation were published on the Department of Industry, Trade and Tourism website. The varied authorisation reduced the security bond to $400,003,226 (a reduction of approximately $120,000million).
8 December 2020 - during a public hearing of the NT Parliament’s Budget Estimates Committee, the DITT’s Executive Director Mines, Mr Armando Padovan stated that the security for the MRM had been reduced from approximately $519 million to $400 million because MRM is going to reduce the “thickness” of the material that will cover the waste rock dump (to prevent the non-benign waste rock from reacting with the elements) from 8 metres to 3 metres.