Study casts doubt on seabed mining prospects
23 November 2011
BY RANDY BOSWELL
WITH NAUTILIS MINERALS now licensed to open the world's first undersea mine off the coast of Papua New Guinea, a new Canadian-led study of whether ocean-floor extraction of copper, gold and other metals is "worth the risk" concludes that accessible supplies of deep-sea resources are not nearly as plentiful as previously believed.
The fresh assessment of offshore mining potential — published in the journal Geology— notes that the copper-gold project proposed by Canada's Nautilus Minerals on the floor of the Bismarck Sea is "adding urgency to the debate about deep-sea mining" at a time when easy-to-reach metal deposits on land have been in extraordinarily high demand.
"The possibility of mining sea floor (deposits) has stirred debate about the sustainable use of this new resource and whether commercial development is worth the risk," the research team states in Geology.
And the scientists conclude that although the vast ocean bottom may well hold massive mineral deposits, the most easily identifiable and accessible seams of copper and zinc along the Earth's "neo-volcanic" ridges, for example, are "insufficient to satisfy a growing global demand for these metals."
Co-author Mark Hannington, the University of Ottawa's Goldcorp Chair in Economic Geology and lead author of the study, told Postmedia News on Monday that while undersea metals are very challenging to obtain, the world's nations "may need (them) someday."
And he said the work Nautilus is doing in PNG is "fantastic, because we've learned so much already about these deposits (from company research) that we as scientists could never have hoped to have learned" given limited university budgets.
But Hannington sounded a note of caution about the overall economic prospects for undersea mining.
"I think the bottom line that the world needs to understand is that the oceans — at least on the neo-volcanic zones where people are presently exploring — are not going to make a major impact on the total availability of metals," he said.
Still, "some companies, like Nautilus, will make a few bucks if they can recover the metals at a cost which is less than that associated with mining on land."
Key to the financial equation, said Hannington, is the rate at which land-based resources become depleted and the costs of extracting metals from the ocean bottom become truly competitive.
"Just in the United States, which is not a major mining centre, there are 90 million tonnes of copper and zinc in the ground that hasn't been developed," he said. "And that's more than all the metal in the deposits that we think exist in the neo-volcanic zones and the ridges" of the oceans.
Hannington positions himself on undersea mining "halfway between those who are rushing and those who are not," he said. "The resources in the oceans are likely to become part of a spectrum of resources that we exploit — just like energy, we exploit wind and solar and oil and gas and nuclear.
"I think that certainly ocean mining is going to take place. But it isn't going to replace current metal inventories from land-based mineral deposits."
He added that the Geology study is "purely about the geological resource and with potential economic implications. It doesn't consider at all the environmental, social, etc. impacts that may result from this activity."
While the government of PNG has given what Nautilus officials call "historic" approval for the undersea project, critics such as Australian senator and Green party leader Bob Brown have raised alarms about the proposed development.
"The Australian Greens are calling for scrutiny of what deep seabed mining means for the health of our oceans and our own country's natural marine resources and fisheries into the future," Brown said in a June statement about Nautilus's proposed "Solwara 1" mining operation, which would take place about 1,600 metres underwater.
Under the Canadian company's plan, robotic mining machines would break up the metal-rich ore on the ocean bottom and send a slurry solution by pipeline to a surface barge for transport and further processing. The technology is largely modelled on offshore oil and gas operations.
Hannington declined to weigh in on the debate about the environmental impact of offshore mining.
"That's not my domain," he said. "That's a question that society and governmental agencies are going to have to tackle to determine whether those risks are acceptable."
Source: Postmedia News / The Vancouver Sun, 21 November
Read more: http://www.canada.com/technology/Canadian+study+casts+doubt+seabed+mining+prospects/5745632/story.html#ixzz1eO8kzyCl
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