McArthur River zinc mine

This article is about the McArthur River Lead-Zinc Mine, Northern Territory, Australia. For the McArthur River Uranium Mine, Saskatchewan, Canada, see McArthur River uranium mine.
McArthur River mine

The MV Aburri transports mineral concentrate from the port to export vessels
Location
McArthur River mine
Location in Australia
Location Borroloola
Territory Northern Territory
Country Australia
Coordinates 16°25′34.81″S 136°04′38.73″E / 16.4263361°S 136.0774250°ECoordinates: 16°25′34.81″S 136°04′38.73″E / 16.4263361°S 136.0774250°E
Production
Products Lead-Zinc-Silver bulk concentrate
Zinc Concentrate
History
Opened 1995
Owner
Company Glencore
Website http://www.xstratazinc.com/ http://www.mcarthurrivermine.com.au/

The McArthur River mine is one of the world's largest zinc, lead and silver mines, situated about 70 kilometres southwest of Borroloola, near the Gulf of Carpentaria in the northeastern Northern Territory, Australia. It is operated by McArthur River Mining (MRM), a subsidiary of the Swiss mining company Xstrata. Although discovered in the 1950s, when it was originally called the HYC ("Here's Your Chance") deposit, it only opened as a mine in 1995. Initially an underground mining operation, the mine has been converted to open-cut.

Economic benefits

2.5 million tonnes of ore containing 383kt of zinc, 93kt of lead and 110t of silver are currently mined per year[1] . Following a comprehensive 16-month study of the environmental impact, a new development project will increase production to 5.5 million tonnes per year. The workforce will increase to 735 by 2020 with a high level of Indigenous participation. The mine will operate until 2038 and will contribute $8.4 billion to the Northern Territory economy and $9.3 billion nationally.

Ore processing

Due to the nature of the complex ore body – extremely fine dissemination of the valuable mineral grains intermeshed with the gangue – the technology to efficiently produce a marketable concentrate from this type of ore was not available until long after the site was known about. After Mount Isa Mines (MIM) successfully introduced the IsaMill, the fine grinding necessary for mineral liberation was available for McArthur River to be developed.

This unusual mineralogy combined with the ore's relatively high lead levels makes the lead and zinc virtually inseparable prior to smelting, and there are very few smelters which can process concentrate which is high in lead. These issues led Mount Isa Mines (later Xstrata) to develop a new lead-zinc leaching process in partnership with Highlands Pacific, known as the Albion process.[2] The first pilot plant based on the Albion technology is currently in the process of expanding to full-scale production in northern Germany.[3]

Transport

Bulk concentrate is trucked 120 km from the mine to a loading facility in the Gulf of Carpentaria.[4] The concentrate is loaded onto a ship at the Bing Bong Loading Facility. From here the purpose-built barge called MV Aburri operates a shuttle service from the loading facility to a point fifteen nautical miles offshore where the concentrate is transferred on to overseas bulk carriers.[5]

Criticism

The change from underground to open pit mining caused controversy in the surrounding communities concerned with heavy metal pollution, and the disruption of the McArthur river itself. The main ore body lies directly beneath the river, so the conversion to open pit necessitated the diversion of the river along a canal that runs around the facility to the east.

A small section of seagrass, which provides food for dugongs, has been destroyed by dredging at the Bing Bong Loading Facility. Potential for bioaccumulation of heavy metals in dugongs, a significant concern for Aboriginals from Borroloola who eat the meat, has been identified as a result from potential ore spillage at the facility.[6]

Environmental impacts

Adverse impacts of seepage from the Tailings Storage Facility (TSF) have been detected in Surprise Creek. Seepage monitoring in 2005 and 2007, as well as measurement and modelling during 2010, clearly shows that soluble sulfate, zinc and, potentially, lead and cadmium are seeping into Surprise Creek. Dust from operations at the run of mine (ROM) pad and crushing plant, and also historically from the TSF, is being expressed in stream sediments in both Barney Creek and Surprise Creek. Both of these chemical inputs from the mining activities have adversely impacted the macroinvertebrates in Surprise Creek.[7] Other remaining issues that the Independent Environmental Monitor considered significant and to require immediate action towards rectification include the volume of water stored in Cell 2 of the Tailings Storage Facility remains a concern as there is considered to be an extreme risk of embankment failure or overtopping of the spillway.[8] The Environmental Monitor's Report for 2010 stated that there were two environmental issues which are considered to pose extreme risks; these are the potential: overtopping of TSF cells leading to an embankment failure; and for acid leachate migration from the TSF into Surprise Creek.[9] In 2010, XStrata reported that 1,862,874 tonnes of tailings were deposited in the Tailings Storage Facility.[10]

See also

References

  1. ↑ http://www.mcarthurrivermine.com.au/EN/mineexpansion/Pages/Phase3DevelopmentProject.aspx Missing or empty |title= (help)
  2. ↑ Pease, Joe (August 2005), "Complex leaching becomes much simpler" (PDF), Australian Mining: 26–32, retrieved 6/01/2010 Check date values in: |accessdate= (help)
  3. ↑ "The Albion Process" (PDF) (Press release). Albion Process. 01-06-2005. Retrieved 6/01/2010. Check date values in: |date=, |accessdate= (help)
  4. ↑ "Production: Shipping". McArthur River Mining. 8 April 2010. Retrieved 23 September 2011.
  5. ↑ "Ships (Capital Grants) Regulations (Amendment) 1996 No. 87". ComLaw. Commonwealth of Australia. Retrieved 23 September 2011.
  6. ↑ Marsh, Helene (2002). Dugong: Status Report and Action Plans for Countries and Territories. United Nations Environment Programme. p. 108. ISBN 92-807-2130-5. Retrieved 17 November 2011.
  7. ↑ Environmental Earth Sciences Vic (2011) Report To The Minister For Primary Industry Fisheries and Resources, Independent Monitor’s Audit Of The Mcarthur River Mine For The 2010 Operational Period, October 2011, Report No. 211011, http://www.nt.gov.au/d/Content/File/p//minergy/MRM_Independent_Monitor_2011_Audit_Report.pdf
  8. ↑ Environmental Earth Sciences Vic (2011) Report To The Minister For Primary Industry Fisheries and Resources, Independent Monitor’s Audit Of The Mcarthur River Mine For The 2010 Operational Period, October 2011, Report No. 211011, at Executive Summary, p.2, http://www.nt.gov.au/d/Content/File/p//minergy/MRM_Independent_Monitor_2011_Audit_Report.pdf
  9. ↑ Environmental Earth Sciences Vic (2011) Report To The Minister For Primary Industry Fisheries and Resources, Independent Monitor’s Audit Of The Mcarthur River Mine For The 2010 Operational Period, October 2011, Report No. 211011, at p.16, http://www.nt.gov.au/d/Content/File/p//minergy/MRM_Independent_Monitor_2011_Audit_Report.pdf
  10. ↑ Xstrata Zinc Australia Sustainability Report 2010, p.36; http://www.mcarthurrivermine.com.au/EN/Publications/Sustainability%20Reports/XstrataSustainability_2010_web.pdf