DURHAM -- On Oct. 20, the island nation of Papua New Guinea opened the door for the world's first private venture to mine massive metal sulfides from the deep sea floor. The permit allows Nautilus Minerals to begin mining for gold and other metals nearly a mile below sea level, in a space roughly the size of 49 football fields, near the hydrothermal vents known as Solwara 1.
While there are risks involved, its overall effects on the environment and economy could be positive if we are careful about how we choose to mine the deep sea.
Deep sea mining shows incredible economic potential for our technology-driven civilization and much of the world's economy. China's recent refusal to provide rare earth metals and the gold mine collapse in Chile highlight both the tenuous state of current metal supplies and the high human cost of conventional mining.
Areas targeted for mining in the deep sea can be five to 10 times more productive than terrestrial mining. This means the same amount of gold that will come from Solwara 1 would require up to 500 football fields of strip mining. On top of this, the environmental impacts of deep sea mining are fundamentally different than the well-understood, and deeply problematic, environmental effects of terrestrial strip mining or even sub-surface gold mining.
For starters, the deep sea ocean environments targeted by Nautilus Minerals are naturally prone to catastrophe. They are volcanic fields that have, do, and will continue to erupt. Each eruption can pave many square kilometers of sea floor. The direct footprint of Nautilus' undersea mine will be noise in an otherwise chaotic undersea cycle of explosion, death, rebirth and growth that marks time on the deep sea floor.
Of course, as we found out with the Deepwater Horizon oil spill in the Gulf, the indirect footprint of deepwater activities can be huge. For deep sea mining, these impacts can include plumes of debris kicked up by mining or created when materials, left over after ore has been extracted, are returned to the sea.
Nautilus Minerals has devised some rather ingenious ways to minimize these impacts, including filtering the sea water removed from sediments and piping it back to the vent field where naturally existing plumes - caused by vent eruption - are already high. They have even offered to move bottom organisms during mining and bring them back again once mining is complete. But Nautilus Minerals may not represent the typical deep sea mining company.
When the International Seabed Authority begins assigning leases for deep sea mining in international waters in April 2011, the door will be open for other companies to begin the exploration and eventual digging on the international sea floor. Though the authority will require environmental impact statements and best practices for lease applicants, it remains to be seen whether these practices will meet the same high standards developed by Nautilus - standards that protect the environment at the cost of profits.
While the Nautilus endeavor at Solwara 1 is a mere pinprick in the globe's deep sea habitat, more widespread mining will certainly have other cumulative impacts. Just how big these impacts could be is unknown, in part, because we know very little about the location, longevity and ecosystems of the deep sea, especially hydrothermal vents.
What we do know about deep sea hydrothermal vents reveals they are ecologically important, supporting snails, mussels, squat lobsters and other organisms that exist entirely without light. Many of these organisms are found nowhere else in the world.
The area to be mined by Nautilus may yield metals with a market value in excess of $300 million, but we should be prudent and measured in the development of deep sea mining so we don't lose critical ecosystems and habitats. Nations and corporations that intend to pursue mining must be required to make deep sea science and exploration a priority. Careful scientific monitoring of these important and fascinating ecosystems needs to begin before mining begins, and continue well after it has ended, in order to understand, mitigate and prevent the negative impacts mining may have on hydrothermal vents and other habitats in the abyss.
Linwood Pendleton is director of ocean and coastal policy at the Duke University's Nicholas Institute for Environmental Policy Solutions.
