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Deep seabed mining could inflict considerable direct and indirect harm – Sabine Christiansen and Sebastian Unger

  • Written by  Sabine Christiansen, Sebastian Unger
  • Published in Opinions
Deep seabed mining could inflict considerable direct and indirect harm – Sabine Christiansen and Sebastian Unger
03 Jun
Dr Sabine Christiansen and Dr Sebastian Unger are senior research associates at the Institute for Advanced Sustainability Studies

You may have heard about minerals on the bottom of the ocean. The UK Government sponsors several exploration contracts for UK Seabed Resources (a subsidiary of the American aerospace and security company Lockheed-Martin) in the Pacific Ocean to look for them. These minerals come from the so-called ‘Area’, the deep seafloor beyond the limits of national jurisdiction and far out in the global ocean.

This ‘Area’ and its mineral resources represent the ‘common heritage of mankind’. The Law of the Sea Convention, UNCLOS (1982) determines that rather than a free-for-all, this last piece of ocean floor outside the jurisdiction of any coastal state belongs to mankind as a whole and shall be administered in such a way that benefits all, considering in particular the needs of developing countries.

A global intergovernmental organisation made up of all 168 UNCLOS signatories, the International Seabed Authority, was made responsible for regulating access to the Area. Its mandate includes not only the development of mineral resources for the benefit of mankind, but also development measures to ensure protection for the marine environment from the harmful effects which may arise from mining-related activities. This includes the prevention of pollution and interference with the ecological balance, and the protection and preservation of the natural resources, flora and fauna of the marine environment and the overlaying water column.

So, what does ‘common heritage of mankind’ mean, and why might there be a problem? The original idea was one of solidarity and transparency, designed to ensure that marine mining could enable newly decolonised developing states to catch up with industrialised states in economic and social development. But it does not appear that the promises encapsulated in the phrase are being honoured.

There is little transparency at the International Seabed Authority, and in the rush to make deep-sea mining viable, neither the provisions relating to the protection of the environment nor the benefit sharing regime have been elaborated on. There is no common vision among relevant actors about the values of the common heritage of mankind, the responsibilities of maintaining resources for future generations or how benefits could best be allocated. The financial regime being discussed currently doesn’t take into account the value of lost ecosystems and it will not generate money for benefit sharing. There is a high risk that mankind will be left with little more than environmental costs.

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These costs can be substantial. Thirty contracts for mineral exploration covering nearly two million square kilometres of seafloor in the Pacific, Indian and Atlantic Oceans have now entered into force. Of these, 18 are for polymetallic nodules, seven are for polymetallic sulphides and five are for cobalt-rich ferromanganese crusts. Each of these mineral types was formed by the accretion of elements from seawater over millions of years and are part of several very special ecosystems: nodules are found on the sedimentary deep-sea floor at 4,000-6,000m depth, sulphides accumulated from precipitates of hot venting fluid at hydrothermal vents, and the crusts predominantly coat the rocks of seamounts. All these environments are located in the subtropical oceans; they are rich in biodiversity, functionally important, and crucially, they are poorly known. Numerous international agreements call for the preservation and protection of biodiversity, while in the Area, states are considering its industrial destruction. The scale of biodiversity loss to be expected from commercial-sized seabed mining is as yet unknown, for different reasons: the affected environments are vast, difficult to explore and costly to survey; there is only basic understanding of the species present and overall ecosystem functioning; and mining technologies are being developed under the veil of intellectual property protection.

Deep Sea MiningDeep seabed mining could potentially inflict considerable direct and indirect harm to ocean ecosystems

However, on top of the accelerating degradation of ocean ecosystems due to the effects of fishing, pollution and climate change, deep seabed mining could potentially inflict considerable direct and indirect harm. For example, a single manganese nodule mining operation requires the digging up of 200-800 square kilometres of deep-sea floor per year for 30 years, and the sediment plumes resulting from these mining activities will affect the wider ecosystem functions in a much larger area. The recovery of mined places cannot be expected.

Given this, what could be the benefit of deep seabed mining to mankind? The most popular argument given by mining proponents is that future generations could benefit because the minerals recovered from the seafloor will foster economic development and enable the transition to low-carbon energy and transportation systems. Current projections assume that a global transition to low-carbon energy technologies globally will lead to an increased demand for certain minerals, at least until the circular economy has developed its full potential. However, new land mines are already under development to meet the demands of renewable energy development (e.g. for cobalt, copper, lithium, rare earths, nickel), and it appears very unlikely that deep seabed mining will replace any of these.

It is true that land mining has a terrible legacy of environmental degradation and social rights deprivation, yet this is due to governance failures that can better be rectified on land than by opening a new frontier in the deep ocean. It appears very unlikely that deep sea mining will replace any of the profitable terrestrial mines.

As there will be no significant financial or other benefit for mankind, nor substantial demand for the minerals recovered from the seafloor – how could the idea of a common heritage of mankind be realised? The deep ocean is a treasure trove of natural wonders and ecological miracles: species with hitherto unknown abilities of survival and complex functions and yet extreme sensitivity to disturbance. Why not save this world from mining, preserve it for future generations while further investigating this inaccessible, dark, high pressure world?

The deep sea is the largest ecosystem on earth, the cradle of life, crucial to combat global warming and – who knows – may be crucial for the replenishment of coastal waters. Maintaining these capacities would be a real benefit for mankind.

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