The National, Wednesday 25th January 2012
THE campaign to prevent environmental damage from experimental deep-sea mining has gone global, reflecting the mounting worldwide concern about this new form of mineral extraction.
Care2, an on-line community of more than 17 million people, has launched an on-line petition asking the United Nations to stop experimental deep-sea mining until the potential impacts are known.
The petition has attracted more than 10,000 signatures in just a few days – more than double its original target of 5000 – and it is still growing, Care2 said in a press release this week.
Papua New Guinea’s pro-mining government of Sir Michael Somare early last year controversially approved the world’s first experimental seabed mine in the Bismarck Sea.
Sir Michael and his administration has since been replaced by Peter O’Neill but the deal signed with Canadian company Nautilus Minerals remains intact.
Nautilus’ preferred partner in the project to develop Solwara-1 is an as yet unnamed Chinese company.
Chinese mining companies are exploring undersea hydrothermal vents in the Indian Ocean, which has sparked international interest into the threat to rare and previously unknown marine species.
Currently, the best potential deep sea site, the Solwara-1 project, has been found in the waters off Papua New Guinea, a high grade copper-gold resource and the world’s first Seafloor Massive Sulphide (SMS) resource.
The Solwara-1 project hosts an indicated resource of 870,000 tonnes, containing 6.8% copper, gold at 4.8 grams per tonne and silver at 23gpt.
There is an inferred resource of 1.3 million tonnes at 7.5% copper, 7.2gpt gold and 37gpt silver.
The copper resources were calculated using a 4% copper cut-off.
The Solwara 1 Project is located at 1,600m water depth in the Bismarck Sea, New Ireland province.
Using the latest ROV (remotely operated underwater vehicles) technology, Nautilus will be the first company of its kind to begin full-scale undersea excavation of mineral deposits.
First production is expected in early 2013.
Nautilus plan to use remotely operated robots equipped with cutting implements to tear up the seafloor into manageable chunks, which will then be pumped to the surface through rigid pipes.
A vessel above will retrieve the material and dewater it. None of the smelting can be done at sea so barges will transport the ore back to land and on to smelting plants where it can be processed.
Because deep sea mining is a relatively new field, the complete consequences of full scale mining operations are unknown, on-line reference site Wikipedia says.
However, experts are certain that removal of parts of the sea floor will result in disturbances to the benthic layer, increased toxicity of the water column and sediment plumes from tailings.
Removing parts of the sea floor disturbs the habitat of benthic organisms, possibly, depending on the type of mining and location, causing permanent disturbances.
Aside from direct impact of mining the area, leakage, spills and corrosion would alter the mining area’s chemical makeup.
Among the impacts of deep sea mining, sediment plumes could have the greatest impact. Plumes are caused when the tailings from mining (usually fine particles) are dumped back into the ocean, creating a cloud of particles floating in the water.
Two types of plumes occur: near bottom plumes and surface plumes.
Near bottom plumes occur when the tailings are pumped back down to the mining site.
The floating particles increase the turbidity, or cloudiness, of the water, clogging filter-feeding apparatuses used by benthic organisms.
Surface plumes cause a more serious problem. Depending on the size of the particles and water currents the plumes could spread over vast areas.
The plumes could impact zooplankton and light penetration, in turn affecting the food web of the area.
Experimental seabed mining is being backed by the European Union, which is funding the Secretariat of the South Pacific (SPC) to develop laws to authorise the mining throughout the Pacific region.
The project has been criticised for disenfranchising Pacific communities.
Pacific civil society has launched its own petition against experimental seabed mining, which is attracting international support.
The Papua New Guinea Mine Watch website argues the Solwara-1 project is so small, the economics do not justify risking the potential environmental impacts.
It said the mine site in the Bismarck sea was tiny compared to traditional land-based mines and would yield comparatively very little copper or gold.
While traditional mines commonly produce hundreds of millions of tonnes of ore, the Solwara-1 mine will produce less than three million.
“This means there is no compelling economic argument for rushing the mine into production while scientific and environmental concerns remain, local people remain opposed and the necessary laws and regulations do not exist.
“Nautilus Minerals, owners of the Solwara-1 mine, say production will last less than two years based on the proposed production of 1.2 million tonnes of ore in year one and 1.8 million tonnes in year two.
“In comparison, the Ok Tedi mine in PNG processes some 22 million tonnes of ore per year and still has resources remaining of at least 350 million tonnes.
“The Ramu nickel mine, meanwhile, has resources of 143 million tonnes of ore and will process at some five million per year.
“Papua New Guinea’s economy, with numerous other mines and the US$17 billion (K35.75 billion) LNG project under construction, clearly does not need Solwara-1 and there is no need to rush into production.
Especially, when Nautilus has yet to announce where the ore will be processed and how it will dispose of the toxic waste material.”