Deep sea mining: the potential convergence of science, industry and sustainable development?

As the International Seabed Authority formulates a range of environmental standards and guidelines for deep sea mining within the coming year, we need to consider how science can best navigate an optimal path towards sustainable metal sourcing on land and in the oceans. Updated August 1, 2021

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The oceans remain a vast but vulnerable frontier for scientific and industrial inquiry. Although often neglected as an immense sink for pollution and plunder, some of the earliest international environmental regulations also involved the oceans. The International Agreement for the Regulation of Whaling was signed in 1937 and is considered the first major multilateral environmental treaty. This agreement was further strengthened by the establishment of the International Whaling Commission and the formalization of the International Convention for the Regulation of Whaling in 1946. Despite the treaty having its ebbs and flows of national membership over the past several decades, the resilience and recovery of the world's largest mammals has been remarkable. A recent study of recovering whaling populations, published in the Proceedings of the Royal Society, showed that the humpback whale population in the southern oceans has gone from a low of 400  in the 1950s to over 25,000 in 2019. 

Nevertheless, the anthropocene continues to bring new challenges and opportunities for ocean conservation. An immediate threat which has garnered world attention with demonstrable impacts is the scourge of plastics pollution that poses to be a mounting menace for oceanic fauna. However, the environmental activist community is also stridently concerned about another potential longer-term threat -- the advent of deep sea mining in coming years. A coalition of over eighty NGOs released a report in May, 2020 on what was presented as a review of the scientific literature on the potential harm of seabed mining activity which is being considered under the United Nations Law of the Sea Convention (UNCLOS). Earlier in the year, Fauna and Flora International published an assessment of their concerns to marine biodiversity from this activity.  

These reports are well-intentioned in their use of the precautionary principle and have received stellar endorsements from great doyens of oceanic conservation such as Sir David Attenborough and Sylvia Earle. However, precaution operates on a spectrum as with any human endeavor, and the principle cannot be used as an excuse for indefinite inertia in a world with competing challenges. Caution is in order but indeterminate precaution is an untenable postulate that can lead to societal paralysis.

For functional purposes, a systems science approach is needed to consider the way forward as the deep sea mining enterprise has to try and optimize four overarching and potentially competing objectives:

a) Comparative environmental and social impact of mining on terrestrial versus oceanic ecosystems;

b) Supply projections for key critical metals from terrestrial ore reserves (economically viable deposits) and resources (geologically available but currently not economically viable deposits); and from recycled sources and more resource efficient practices;

c)   Demand projections for critical metals needed for the transition to cleaner energy sources such as wind and solar power as well as for batteries for electric vehicles and smart-grids;

d) Revenue generation potential for sponsoring Small Island Developing States (SIDS) who are partnering with industry for deposit exploration.

This is a momentous year for the International Seabed Authority (ISA), which was formed over two decades ago as part of the United Nations Law of the Sea Convention, and is planning to release a set of environmental standards and guidelines related to the implementation of its mining code.  In this article, I provide a review of some of the key issues that can help to extricate the points of contention for more informed decision-making.

Comparative ecological impact categories

There are a range of ecological impacts which are a point of conservation concern around deep sea mining and vary from the kind of location where mining is to occur. Mineral deposits in the deep seas can be found in i) polymetallic nodules on the seabed; ii) seamount metallic (ferromanganese) crusts; and iii) sulfide deposits in extinct hydrothermal vents.  Currently  18 exploration contracts have been granted for polymetallic nodules in the Clarion-Clipperton Fracture Zone (16), Central Indian Ocean Basin (1) and Western Pacific Ocean (1). There are 7 contracts for exploration for polymetallic sulphides in the South West Indian Ridge, Central Indian Ridge and the Mid-Atlantic Ridge and 5 contracts for exploration for cobalt-rich crusts in the Western Pacific Ocean. Of these systems, the gravest concern of impact is near hydrothermal vent sulfide deposits. Notably the scaly-foot snail (Chrysomallon squamiferum), is found exclusively on three hydrothermal vent systems in the Indian Ocean at depths of over 2,400 m, and was placed on the International Union for Conservation of Nature (IUCN) Red List in June 2019 due to two of the three systems falling within the boundaries of exploratory mining licenses granted by the International Seabed Authority.

However, the most advanced mining exploration that has moved forward thus far and shown to be economically viable is largely focusing on polymetallic nodules, which occur in arguably the least species diverse of the three ecosystems. No doubt, the ecology around these nodules is unique and all activities must proceed with great care regardless of absolute diversity estimates thus far. In particular, the microbes which are believed to have led to the accretion of the metallic deposits pose a fascinating area for research in terms of their pharmacological properties. To this end, the industry and the ISA has committed to only allowing for mining to occur if there are two "reference zones" which have been allocated for conservation purposes and for impact measurement purposes of at least equivalent size. Although some conservationists have questioned the efficacy of the concept of "no net loss", we undertake this approach constantly through protected areas management on land and in the oceans. A lot of the efficacy depends on the level of homogeneity of particular systems. Thus coral reefs and active hydrothermal vents which are highly heterogeneous systems are not appropriate for such an approach but the vast deep sea nodule plains may well be so. The characterization of these reference zones is an important protective feature that is now being studied in detail. Notably, an equivalent protective feature of this kind is not generally required in terrestrial mining sites that may occur in potentially even more biodiverse and vulnerable ecosystems such as rainforests.

Ultimately, the environmental impacts will need to be considered as a comparative life cycle assessment between terrestrial and oceanic minerals. Such an assessment has been undertaken and published in a peer-reviewed well-ranked journal (I am a contributing author to this study along with Steve Katona, cofounder of the Ocean Health Index). Separate peer-reviewed studies have provided a framework for looking at the full impact considerations, which are likely to be less than terrestrial mining, largely owing to minimal processing energy requirements. Even more significantly, the waste generation and hazard of tailings dams that come from terrestrial mines is mitigated in the case of oceanic minerals. 

Assessments of the discharges from the shipping vessels that undertake initial processing of the ore residues, as well as the plumes of sediment generated along the water column as the minerals are retrieved to the surface are still to be fully evaluated. A team led by Thomas Peacock at MIT has undertaken some of this research for the International Seabed Authority and published findings in July 2021. Studies from earlier deep sea disturbances that occurred in the 1970s and 80s during often clandestine exploration activities without any mitigation measures are not a suitable comparison (though can inform the standards development) with the current state of equipment and technology being tested. The same can be said of older techniques for terrestrial mining compared with modern practices.

Another area of concern that has been noted by some activists pertains to accidental methane releases from hydrate deposits in the deep sea which could contribute to carbon emissions. The temperature, pressure and geochemistry of the region of the ocean where current mining is being considered so far does not appear to be a point of concern in this regard. Furthermore, methane extraction itself as a resource remains a point of consideration and if there was such a concern, it could potentially be harnessed as a resource, or for mitigation purposes.

Comparative social impacts and lessons from the Nautilus venture

The social impact comparisons of oceanic mining with terrestrial mining equivalents are far more clear in terms of evaluation. Most significantly, there are no major concerns of human rights abuses, child labor, human trafficking or property appropriations and resettlement that beset many terrestrial mining conflicts. Of course the broader fishing and shipping industry has these social afflictions but the detailed oversight of all DSM vessels would prevent their prevalence in the sector. An area of potential social contention is the interaction between DSM activities and fisheries which could indirectly have social consequences. However, the single biggest threat to fisheries is commercial and often illegal fishing of vulnerable stocks. The impact of DSM on fisheries should certainly be monitored closely as the infrastructure is tested. There are also some interesting comparisons on fisheries in terms of noise and infrastructure development that can be compared with the oil and gas sector with which we have considerable long-term experience of measuring impacts. With oil and gas infrastructure there is far greater danger of catastrophic failure and large leaks or explosions from the deposit itself. However, the precautionary principle has been largely undermined in this context by major OECD countries for energy resource expediency.

Another comparison that is often raised with reference to social concerns about deep sea mining, is a comparison with the beleaguered Solwara 1 project by now defunct Nautilus Minerals. The demise of that project was due to a combination of investment flight and social concerns and opposition from coastal communities in Papua New Guinea, under whose maritime jurisdiction the project was being developed. None of those particular concerns would be applicable in remote parts of the ocean where deep sea mining is being developed. A plausible point raised by activists is that the environmental mitigation code being considered by the ISA a decade ago was to be modeled after the proposed measures from the International Marine Minerals Society. However, the current deliberations on the code are highly divergent and are more likely to consider best practices from the oil and gas sector as well as the maritime diamond mining sector operating off the coast of Namibia. 

There is also a financial concern that is often noted about poor small island states investing in seabed mining and losing precious public funds in such ventures. For sure, caution is in order as there have been some heinous cases of poor extractive industry investments spurred on by misleading forecasts of fortune. However, there are numerous financial safeguards and wealth distribution mechanisms under the "common heritage of humankind" provisions of the Law of the Sea Convention in this regard. Furthermore, the minerals being extracted are the antithesis of fossil fuels in terms of their potential support for solving the climate crisis. Thus oceanic minerals have far greater chance for future market security than the conventional terrestrial stranded assets that are causing concern among development practitioners. Furthermore, the COVID crisis has led many small island states to consider ways of diversifying their economies, since reliance on tourism is so highly capricious in terms of extreme weather events or global emergencies such as the current pandemic. A country like Nauru, which has a tragic history of phosphate mining plunder on its territory, has invested in deep sea mining as a diversifying off shore investment, that would not have a direct ecological impact on its inhabitants.  A detailed cost-benefit analysis of manganese nodules extraction for the Cook Islands conducted by the European Commission and the Pacific Community (SPC) suggested a net benefit of over $494 million over the life of a potentially feasible project.

Mineral demand and supply scenarios

The potential for stranded investment concerns stems often from debates in the literature related to the future demand for specific oceanic metals such as cobalt, nickel and manganese. Commodity prices fluctuate wildly and this can arguably have impact on the fortune of resource dependent economies, though strong institutions have shown to offset these effects. In any event, the latest demand scenarios indicate that substitution for the key metals that could be extracted from nodules is unlikely to occur because of fundamental electrochemical advantages of those elements and existing infrastructure investment in their manufacturing. Substitutes for copper have been predicted for decades and even after the advent of fiber optics cables that took a bite out of copper demand, the metal's need remains salient. Even if alternatives are found, the appliance or device intake for batteries is modular, and having a variety of products using different kinds of metal electrodes would be advantageous and lead to more resilience in the system. 

Recycling of batteries and the potential for a circular economy are also important future supply sources for these metals. In China, "urban mining of metals" for recycling may well meet some aspects of demand. However, a range of scenarios studied by the World Bank in their most recent assessment indicate that recycling would not be able to meet demand needed for green technology uptake to reach the climate mitigation targets. Recycling also poses an intriguing sustainability challenge since in order to have stock for recycling it becomes necessary to make existing infrastructure more obsolescent. Overall such an outcome may be worse in terms of sustainability metrics if there is too much focus on recycling primacy without a mix of supply sources.  Furthermore, in terms of the development impact of the metals being harnessed by small island states could also merit them being preferentially sourced, which in some cases might even justify a development premium for consumers. Opportunities for metal stockpiling can also modulate price shocks and unlike agricultural products there is no "shelf life" challenge for long-term storage.

Institutional context and errant comparisons

The prospect of a positive premium for deep sea mining metals seems very remote at present since it is instead being stigmatized by several civil society groups as a potential ecological threat. Unfortunately, the current polarization is a result of a lack of trust with institutions managing the process, particularly the International Seabed Authority. Criticism of the organization rests on its dual mandate to facilitate development while also regulating activities. There have been numerous proposals for improving the transparency of the organization's activities which deserve attention. In particular the Legal and Technical Commission of the organization could be an area where further reform could help to build trust with environmental organizations and activists. Having greater independent governance and oversight of this committee could be considered within the framework of the UNCLOS mandate.

However, such reform, nor the need for further biological research, seem appropriate grounds to call for a moratorium on exploration licenses for deep sea mining. Comparisons with the moratorium under the Antarctic Treaty are not congruent since Antarctica has competing territorial claims and there is no corollary body of oversight and due diligence for mineral exploration similar to the ISA. Furthermore, there has in fact been a de facto moratorium on deep sea mining for the past 20 years even though technology had been developed for such activity going back at least 3 decades. The hiatus in development was largely owing to deliberative processes and research to address many of the concerns already raised and in the process of being addressed through the regulatory process. Any mining licenses, following viable reserves being found, would take several more years to develop in any case.

We are at a momentous time of the great energy transition alongside the need for diversification of oceanic economies of states. There are also international legal mechanisms for biodiversity protection which are emerging specifically for oceans, such as a new treaty for marine protection, alongside work by the High Level Panel on Oceans. Concerns over marine pollution from the surface activities of DSM would fall under the existing International Convention on the Prevention of Marine Pollution from Ships (MARPOL). There are broad conservation monitoring guidelines which have already been widely studied in recent literature, though the role which mineral exploration can play in resourcing such programs deserves greater attention.

The way forward for sensible conversations

Oceanic minerals development needs to be considered as part of a socio-ecological conversation about planetary sustainability at supply and demand nodes. Epithets such as "extractive capitalism" are also not appropriate for an activity which is in fact being undertaken through an unprecedented public-private partnership for global revenue sharing. Even though the activity will be far from any human habitation, there is still a presumption by some opponents of its impact being linked to social concerns on land. However, such discourse is holding the industry to a standard not even terrestrial mining is held to in terms of the locus of impact and legitimacy of community dissent. The level of global deliberations that are being carried out in this regard provide us with a rare opportunity to be proactive in environmental regulatory action rather than reactive

The environmental movement should learn some of the lessons of its absolutist opposition to nuclear power which led to industrial research stagnation and a lost opportunity for climate mitigation because of extreme risk aversion. Resilience of natural maritime systems, even after nuclear exposure also needs to be considered. In the Bikini atoll where 23 nuclear tests were conducted (including the largest ever nuclear explosion), biodiversity studies conducted fifty years hence show remarkable recovery. Of course the social consequences of this testing were immense but that is precisely why it is important extricate social and ecological impacts in the high seas. Allowing for this frontier industry to cautiously proceed with careful monitoring and governance reform of the International Seabed Authority would be the sensible way forward for meeting the Sustainable Development Goal and targets related to the oceans (SDG 14, particularly Targets 14.7, A, B and C).

Civil society, industry and governments should also be willing to give each other some benefit of the doubt in this frontier area of human endeavor that by its very structure seeks such deliberative outcomes. Of course there is pressure to develop prospects without undue delay due to investors having already put funds into particular ventures. Yet, such investment should be used as an opportunity to keep momentum in exploring the deep seas and harnessing resources where overall ecosystem integrity can be conserved. It is no wonder then that notable ocean conservationists, such as Steve Katona (cofounder of the Ocean Health Index), who have devoted their lives to the deep sea, are willing to consider this quest as a potential win-win opportunity that deserves a chance.  Such professionals should not be blamed or shamed for engaging with industry or governments any more than environmentalists should be blamed for taking large donations from deep-pocketed conservation tycoons. Reasonable well-intentioned people can disagree about risk trade-offs and come to different conclusions and resource their endeavors accordingly. Last year's very relevant Nobel Prize in Chemistry, for the invention of the lithium ion battery, shows us that good science can come from industry, government and academia working together (the prize was shared by an industry scientist and two academics, one of whom had also worked for government). No one should make up their mind yet on the ultimate viability of this major planetary activity but our debate should be based on science and due process of deliberative engagement with broader needs of society. 



Saleem H. Ali

Blue and Gold Distinguished Professor of Energy and the Environment, University of Delaware and GEF Science Panel

Saleem H. Ali is the Blue and Gold Distinguished Professor of Energy and the Environment at the University of Delaware (joint tenured appointments in Geography and the Joseph Biden School of Public Policy); Senior Fellow at Columbia University's Center on Sustainable Investment; and Honorary Professor at the University of Queensland (Australia). He is also a member of the United Nations International Resource Panel and the Scientific and Technical Advisory Panel of the Global Environment Facility. His latest book is Earthly Order: How Natural Laws Define Human Life (Oxford University Press, 2022) Twitter @saleem_ali