As green technologies to reduce carbon emissions proliferate around the world, the demand for the critical minerals needed to produce them is growing. They are increasingly expensive to mine and their deposits are concentrated in a few countries, posing a risk to global supply. Many believe that the solution lies deep under the sea, as critical minerals are found in large quantities on ocean floors and seabeds. The emerging deep-sea mining aims to exploit these minerals, but it is highly controversial, even though it has not even started yet. This analysis will look at the reasons for this, the debate on the ongoing formulation of the regulation of deep-sea mining in international waters, the position of the European Union and its member states, and the doubts about the realisation of and prospects for deep-sea mining.
The discovery that there are mineral-rich nodules in the depths of many seas that could potentially be exploited was made in the 1870s by a Scottish chemist called John Young Buchanan during the Challenger expedition, which marked the beginning of modern oceanography. Almost a century later, in 1965, John L. Mero’s book The Mineral Resources of the Sea was published, and was central to the concept of deep-sea mining (Dive and Discover, 2024; Cronan, 2015). The nascent deep-sea mining industry is emerging as a promising opportunity for many countries and companies as the green transition becomes more important, but its controversial nature has also led to growing opposition.
What is deep-sea mining?
What is it all about? Deposits rich in critical minerals such as cobalt, nickel, copper and manganese are found on the seabeds and ocean floors in many parts of the world. These minerals are important components of mobile phones and other computing devices, among other things, and play a key role in the green transition as they are essential components of the technologies needed for it, such as batteries for electric vehicles, solar panels and power grids. Marine deposits fall into three categories:
- Polymetallic nodules – these formations, typically between 2-8 centimetres in size, cover vast areas of the ocean floor. They are most abundant in the area between Hawaii and Mexico, known as the Clarion-Clipperton Zone, in the central Indian Ocean, and in the south-eastern Pacific Ocean in the Peru Basin, at depths of 4,000-6,000 metres. They are composed mainly of manganese, iron, silicates and hydroxides, but also contain nickel, copper, cobalt and rare earth elements (International Seabed Authority, 2024e).
- Polymetallic sulphides – over the past decades, more than 350 high-temperature hydrothermal vents (i.e. fissures where magma meets seawater) and around 200 sites with significant massive sulphide accumulations have been identified, containing large amounts of copper, zinc, lead, iron, silver and gold. The majority of these deposits are associated with mid-ocean ridges, submarine volcanic arcs and adjacent basins (International Seabed Authority, 2024f).
- Cobalt-rich ferromanganese crusts – they occur at shallower depths of between 400-5,000 metres in areas of significant volcanic activity. In many cases, the deposits are found in countries’ exclusive economic zones. The crusts contain nickel, manganese, cobalt, platinum and rare earths (International Seabed Authority, 2024d).
All three types of deposits can be found worldwide, but only a fraction of them is considered economically exploitable. Deep-sea mining, which has not yet started but is expected by some to start within a few years, focuses on nodules, as they seem the most technically feasible to extract (sulphides and crusts would be extracted using processes similar to onshore mining, but this would be more difficult to do underwater) (Chung, Scheyder and Trainor, 2023).
Billions of tonnes of polymetallic nodules are estimated to be found at the bottom of the seas (Lu, 2023). The Clarion-Clipperton zone contains more nickel, cobalt and manganese than all onshore deposits and roughly as much copper as all onshore deposits (Chung, Scheyder and Trainor, 2023). The Canadian The Metals Company (TMC), the most technologically advanced deep-sea mining company, estimates that the area they intend to mine contains enough polymetallic nodules to produce 280 million car batteries (Halper, 2023).
Several companies have already collected small amounts of nodules as part of their experiments (Chung, Scheyder and Trainor, 2023). The main concept regarding the method of collecting nodules is currently to lower a robotic vehicle to the seabed to collect the nodules along with the top layers of sediment. The collected material would then be transported up to a ship for processing and the waste, such as sediment and other organic material, would be returned to the water (Ashford, Baines, Barbanell and Wang, 2024).
Potential harmful consequences
Deep-sea mining is a highly controversial issue, as it raises serious and as yet unanswered questions about its impact on (deep) marine ecosystems. We know very little about the deep seas, the last unexplored part of the Earth – less than we know about the surface of the Moon (Gill, 2024). Long thought to be lifeless due to extreme conditions – lack of sunlight, extreme pressure, cold –, the deep-sea environment is now known to be populated by up to millions of species (of which we currently know only a few tens of thousands) (Ashford, Baines, Barbanell and Wang, 2024). Since we have almost no knowledge of these ecosystems, we do not know how destructive deep-sea mining would be for them. The following concerns arise:
- Direct damage to marine life – there is a high probability that less mobile deep-sea organisms would die from direct contact with mining machinery on the seabed, and that organisms would drown in the sediment clouds that the machinery would likely stir up. Warm mining waste water can also kill marine life through overheating and poisoning.
- Long-term disturbance of species and ecosystems – mining activities can harm the feeding and reproduction of deep-sea species by causing intense noise and light pollution in a dark and quiet environment. Since many deep-sea species are rare, long-lived and slow to reproduce, and polymetallic nodules provide important habitat for some deep-sea species, it is virtually certain that habitat loss due to mining would threaten some species with extinction. These ecosystems would take an extremely long time to recover, if they ever did.
- Potential impacts on fishing and food security – waste discharges from mining vessels can travel long distances, up to several kilometres, from mining areas. This could pose a threat to pelagic fish and other species that are vital to international fisheries. For example, tuna stocks, which underpin the economies of many Pacific Island nations, including Kiribati, Vanuatu and the Marshall Islands, could be at risk.
- Economic and social risks – although extraction would take place at sea, deep-sea mining would also require onshore facilities, both for processing and for transshipment of the minerals extracted. This would require land acquisition and development, and experience shows that this leads to habitat loss, which affects coastal communities dependent on marine resources the most.
- Potential climate impacts – the oceans are the world’s largest carbon sinks, sequestering around 25% of all carbon emissions. Microscopic organisms play a critical role in this climate regulation system, helping to sequester carbon at the bottom of the oceans and reducing emissions of other greenhouse gases such as methane from seabed sediments. Biodiversity loss from deep-sea mining can affect the carbon cycle in the oceans and reduce their contribution to mitigating global temperature rise (Ashford, Baines, Barbanell and Wang, 2024).
- Concerns about oxygen production – a recent discovery suggests that polymetallic nodules produce oxygen by breaking down seawater into hydrogen and oxygen by the electric current they generate. Deep-sea mining would therefore also threaten life dependent on seabed oxygen, and could even affect atmospheric oxygen, as the oceans provide about half of the oxygen in the Earth’s atmosphere (Gill, 2024).
Further research is needed to understand more fully the potential impacts and risks listed. Many experts, governments and companies believe that until we have a clearer picture of what deep-sea mining would entail, a moratorium should be imposed. This is the demand of nearly 830 marine scientists and policy makers from more than 44 countries in a joint statement, as well as Google, the world’s second largest mining company, Rio Tinto, and (as we will see below) some car manufacturers (Deep-Sea Mining Science Statement, 2024; Chung, Scheyder and Trainor, 2023).
Arguments for deep-sea mining
Proponents of deep-sea mining argue that it can help meet the world’s demand for critical minerals, which will grow as countries step up their efforts to reduce their carbon emissions. According to the International Energy Agency, to achieve carbon neutrality, the world will need at least four times today’s amounts of metals found in polymetallic nodules. There is no consensus on whether critical minerals that can be extracted on land are available in sufficient quantities, but it is a fact that they are becoming increasingly expensive to mine, their economical extraction will become more of a problem, and scaling up mining and processing operations in ways that minimise environmental and social damage will be a challenge (Ashford, Baines, Barbanell and Wang, 2024; Chung, Scheyder and Trainor, 2023).
A further argument for deep-sea mining is that it would avoid the environmental damage caused by surface mining, which also affects people living near mines, for example through deforestation and pollution of drinking water sources. Opponents say this argument is false, as deep-sea mining would not replace onshore mining, but supporters argue that even then deep-sea mining would be less damaging than onshore mining.
Its supporters say it is also an argument in favour of deep-sea mining that onshore deposits of critical minerals are concentrated in a few countries, increasing supply risks. The Democratic Republic of Congo, for example, is one of the countries with the largest cobalt reserves, but some parts of the country are mired in conflict (Stallard, 2024). China’s position is unique because of its dominance in critical minerals and its relevance to the growing tensions between the West and China, as discussed below.
A typical electric vehicle requires six times more critical minerals than an internal combustion engine vehicle
The figure can be referenced here: https://public.flourish.studio/visualisation/20491151/
The figure can be referenced here: https://public.flourish.studio/visualisation/20491336/
International regulation
Any country can approve deep-sea mining in its exclusive economic zone. However, most of these minerals are found in international waters, and their extraction requires international regulation (Ashford, Baines, Barbanell and Wang, 2024). This regulation does not yet exist; the International Seabed Authority (ISA), which is responsible for its development, has been working on its creation since 2016 and it is currently expected to be ready by 2025 (Woody, 2023b; Lu, 2024b). The ISA is the organisation through which states parties to the United Nations Convention on the Law of the Sea (UNCLOS) are to organise and control mineral resource activities in the so-called Area, which covers about 54 percent of the world’s total ocean area and, together with its resources, is the common heritage of mankind, in a way that benefits all of humanity. ISA’s mission is to ensure the effective protection of the marine environment against potential adverse impacts from seabed-related activities. Based in Jamaica, the Authority has 169 members (168 member states and the European Union), according to the latest figures from May last year (International Seabed Authority, 2024a).
Deep-sea mining is banned in international waters until the ISA finalises the rules governing the industry (which should include how developing and landlocked countries will share in the royalties, as one of the principles of the ISA is that seabed resources should be shared globally [Shukman, 2014]). In 2021, however, Nauru and its sponsored deep-sea mining company, TMC, got fed up with waiting (private companies wishing to mine need a sponsoring ISA member state; TMC’s sponsors are Nauru, Kiribati and Tonga). Nauru, citing a UNCLOS rule, gave the ISA a two-year timeframe to establish mining regulations. As the ISA was not ready with them in 2023, since the deadline has passed, countries and companies can apply for mining permits even in the absence of regulations (Lu, 2024a). The first company to do so, TMC plans to submit a mining application this year, which is expected to take a year to be processed (Stanway, 2024).
Diverging views on regulation
The ISA has signed 31 fifteen-year contracts with 22 partners for exploration relating to deep-sea mining (but not mining itself), including governments (India, South Korea, Poland, and a Russian ministry) and state organisations (linked to, for example, China, Russia, Germany, France, India and Japan) (International Seabed Authority, 2024b). However, there is no consensus within the ISA on how to regulate mining activities. While some countries, such as Japan, China, Norway, Nauru, the Cook Islands and Papua New Guinea, support deep-sea mining (Glosserman, 2024), more than 30 countries have expressed some form of opposition. France would ban deep-sea mining. Canada, New Zealand, the United Kingdom, Switzerland, Fiji, Palau, Samoa and others are calling for a moratorium, while Brazil, Chile, Panama, Tuvalu and Vanuatu, among other countries, would prefer a precautionary pause (Deep Sea Conservation Coalition, 2024). Notably, there is a sharp divide among Pacific Island countries: while Nauru, the Cook Islands and Kiribati, for example, see great potential in deep-sea mining, Fiji, Samoa, Palau, Vanuatu and other countries in the region are calling for a moratorium or precautionary pause.
The authorisation–moratorium/ban opposition also arose in relation to the leadership of the ISA, as a Secretary-General election took place in July. There were two candidates: British lawyer Michael Lodge, the current Secretary-General (in office for eight years), who was widely believed to have too close ties to mining companies, and Leticia Carvalho, a Brazilian oceanographer who believes the ISA must create regulations before deep-sea mining can begin. In the vote, Lodge, who described the impacts of mining as “predictable and manageable”, lost out to Carvalho, who called for more research from sources independent of mining companies. At the heart of the leadership contest between Lodge and Carvalho was the debate that is also the key question for the whole nascent industry: should countries and companies move forward as quickly as possible to exploit the oceans’ mineral resources to make the green transition as fast as possible, or do we need more time to understand what the impacts of deep-sea mining might be (Lu, 2024b; International Seabed Authority, 2024c)?
The position of the European Union and its member states
As far as the European Union is concerned, the attitude of the European Commission and some of the member states has changed significantly over the last ten years or so. In a publication in 2012, the Commission was still positive about the potential of deep-sea mining, and over the next decade the EU spent more than €100 million on deep-sea mining-related expenses to “unlock the untapped potential of Europe’s oceans”. However, in a 2018 resolution, the European Parliament called on the Commission and member states not to support deep-sea mining because of the concerns detailed earlier. As a result, the EU Biodiversity Strategy, published by the Commission in 2020, takes the position that deep-sea mining should not be started without sufficient understanding of its impact on the marine environment, biodiversity and human activities, and the availability of technologies that are only moderately damaging to the marine environment (Seas At Risk, 2024).
Although the Commission and Parliament now have essentially a common position, there is no common EU position. The EU, as a party to UNCLOS, has voting rights in the ISA, but no mandate to take a position on behalf of member states, so it is mostly a silent observer. However, some EU institutions have taken action against deep-sea mining; for example, the European Investment Bank, in a guideline adopted in 2022, lists deep-sea mining as an excluded activity because it is “unacceptable from a climate and environmental point of view” (Seas At Risk, 2024).
As for the individual EU member states, according to a survey by Seas At Risk, a group of European environmental organisations, seven member states are in favour of a precautionary pause, France (as mentioned above) would prefer a ban and Poland is in favour of mining. The other member states, including Hungary, have no clear or official position on the issue (Seas At Risk, 2024).
Great power rivalry
Deep-sea mining is also an arena for (great) power rivalry. Of the exploration permits issued by the ISA, China has the most, five; Russia has four; and India, which has two, applied for two more earlier this year. The US cannot participate in the rush for mining in international waters because it has not ratified UNCLOS. Instead, it aims to obtain critical minerals from its own waters and to process minerals mined by its allies in international waters (Khadka, 2024).
China plays a dominant role in the world’s critical mineral extraction and processing. It is the main producer of nearly 30 critical minerals and, although it is not the main producer of the most important electrical battery raw materials (lithium, cobalt, graphite), it buys, processes, refines and exports them in such quantities that it is also an inescapable player in regard to these materials (Coyne and Bassi, 2024). There have also been examples of Beijing stopping or restricting exports of materials for advanced technologies for political reasons, for instance when it restricted exports of gallium and germanium used in semiconductor manufacturing last year (Reuters, 2023).
However, deep-sea mining could result in the end of China’s monopoly on the market for critical raw materials, which would be welcomed by the rest of the world, especially the United States and the West. China, of course, is interested in maintaining its current position. In the ISA, it advocates creating regulations as soon as possobile and, although it lags behind in terms of expertise and technology in deep-sea mining, it has recently put more emphasis on this field. China wants to be ready to exploit the potential of mining when the time comes (Lu, 2023).
In addition to the above, the global importance of politically and economically marginalised countries can be enhanced if their marine resources become available on world markets. For example, it is estimated that there are cobalt reserves in the deep waters of the Cook Islands equivalent to three times the onshore reserves, which would meet world demand for 80 years. Exploiting the deep-sea mineral resources of similar countries could change their position in the world (Glosserman, 2024).
Cautious car manufacturers
It is not only states that oppose deep-sea mining before we have sufficient information about its impacts and risks. Some carmakers, including BMW, Renault, Rivian, Volvo and Volkswagen, support a moratorium, while GM, Ford and Daimler currently have no plans to use deep-sea resources in their supply chains. The explanation for this approach, which may seem surprising at first, is obvious: car manufacturers do not want their electric vehicle batteries to be associated with even more negative environmental and social impacts (deforestation, pollution, human rights abuses, child labour, deaths from mine collapses). If deep-sea mining is found to be destroying the deep-sea environment once it starts, it would also reflect badly on car manufacturers using the minerals extracted (Halper, 2023).
Deep-sea mining in national waters
In January this year, Norway became the first country in the world to approve mining in its waters. The government stresses that applications (which must include environmental impact assessments) will be assessed on an individual basis. In November last year, 120 EU lawmakers sent an open letter to the Norwegian parliament calling on it to reject the approval, and the Norwegian Institute of Marine Research opposed the decision as well (Stallard, 2024). Japan wants to start deep-sea mining in its exclusive economic zone by the end of the 2020s, and the Cook Islands will decide in 2027 whether to allow mining (Giseburt, 2024; McKenzie, 2024). India’s specific plans are not known, but the country’s National Institute of Ocean Technology already tested its own mining machine in the Indian Ocean in 2022. India has also signed an agreement with Russia to develop deep-sea mining technologies (Khadka, 2024).
Doubts
Its supporters say deep-sea mining has huge potential, but there are questions about it. First and foremost is whether the technology currently exists, or will exist in the near future, to make deep-sea mining feasible. Some companies and states have invested a lot of money in developing their mining technology and are confident that their method will work. However, a famous deep-sea explorer and private equity investor, Victor Vescovo – the first person to descend into the deepest trenches of the world’s five oceans back in 2019 – is convinced that mining operations at depths of thousands of metres are not possible (Woody, 2023a).
Even if mining proves to be technically feasible, the development of battery technologies, a major use of critical minerals, could be a problem. It is possible that deep-sea mineral deposits will lose their attractiveness as alternative battery technologies that do not rely on such minerals become more common. For example, the shift from nickel-manganese-cobalt oxide (NMC) batteries to lithium iron phosphate (LFP) batteries may continue, given that LFP batteries have gained significant market share since 2015; their main materials, lithium and iron, are not targets for deep-sea mining (Ashford, Baines, Barbanell and Wang, 2024).
New technologies such as sodium-ion batteries could also have the potential to transform the electric vehicle battery market, as they use cheaper and more abundant materials instead of lithium and cobalt (Ashford, Baines, Barbanell and Wang, 2024). In the longer term, it is also possible that mass production of solid-state batteries, which have consumed billions of dollars over decades but still exist mostly in laboratories, will eventually take off, and since such batteries do not require the minerals that deep-sea mining can extract, their proliferation could also undermine its economics (Thaler, 2022). As an associate professor at Colorado School of Mines put it, “It is hard to call anything in a battery right now crucial for the future of automobiles” (Halper, 2023).
Summary
Deep-sea mining, which has not even started yet, raises difficult and unanswered questions, in addition to those already mentioned. For example, it is not yet known when actual mining will start. As far as the waters under national jurisdiction are concerned, this will probably happen first in the Norwegian Sea, potentially within a few years. As for international waters, TMC is expected to be the first company to apply for a mining licence this year, but of course there is no guarantee of approval at the end of what is expected to be a year-long assessment process. The question is what will happen if the ISA does not finalise regulations in 2025 and TMC is granted a permit.
It cannot be ruled out that mining will start even in the absence of regulation. In that case, will mining companies be able to sell the minerals extracted (and if so, in the quantities required)? Of course, this question will still arise if regulation is in place, because even if regulation is established next year, it is unlikely that we will know much more about the environmental impacts of deep-sea mining by then, meaning that many potential buyers may still be wary of deep-sea minerals. Staying with regulation, is it possible to design the rules in such a way that deep-sea mining meets the UNCLOS objective of promoting sustainable economic development, international cooperation and equitable increase in trade for all countries?
There are thus many questions surrounding the nascent deep-sea mining industry, and at the moment it can only be said that many different and widely divergent outcomes relating to it can be imagined.
