The Deep Sea Seems to be Opening for Business. Should It Be?
Humans have been pulling resources from the sea for centuries. The Faroe Islands mined their foreshore to build the lime casing of their cathedrals in the 1300s. Namibia has mined alluvial diamonds from coastal waters since the 1800s. The idea of going to sea to source the materials we need is not new. What is new – and fiercely contested – is the prospect of doing so at industrial scale, in international waters, thousands of metres beneath the surface.
That debate reached a new intensity this month. On 9 March 2026, the International Seabed Authority (ISA) – the UN body responsible for regulating mineral extraction in international waters – convened its latest round of negotiations in Kingston, Jamaica, set to conclude on March 20th1. In parallel, The Metals Company announced that the USA’s The National Oceanic and Atmospheric Administration (NOAA) had determined its consolidated application for a deep-sea mining exploration licence and commercial recovery permit to be in substantial compliance with US regulations2 – a landmark step in a domestic permitting pathway that bypasses the ISA entirely.
The timing is not coincidental. It illustrates the central tension now defining the deep-sea mining debate. This is a potentially globally significant resource, governed by an international framework that has spent decades negotiating without resolution, now being pursued through unilateral national action.
What Are They Looking For?
The primary targets are polymetallic nodules – potato-sized mineral concretions found at depths of 4,000 to 6,000 metres. There are found in their greatest abundance in the Clarion-Clipperton Zone (CCZ) in the Pacific (see figure below), and contain nickel, cobalt, copper and manganese, among other minerals.
Alongside polymetallic nodules, the seabed also holds seafloor massive sulphides (found at hydrothermal vents), ferromanganese crusts, and REE-enriched muds. The crust structure, rich in tellurium and rare earths, present the greatest technical challenge as these rocks are strongly cemented to their substrate, requiring energy-intensive blasting and extraction, and hosting biodiversity that is directly tied to the resource itself.
The Debate
Whilst it is almost impossible to contest the arguments for and against deep sea mining in such a short article (and is likely redundant to look at it through a simple yes vs. no lens) the debate over deep-sea mining increasingly centres on whether the strategic and economic case for collecting polymetallic nodules can justify the environmental uncertainties of disturbing the abyssal seafloor.
Supporters argue that the environmental impacts of modern nodule collection may be far smaller than critics assume. Critics, however, argue that these findings are insufficient to establish that these activities are ecologically safe in an ecosystem will still have huge amounts to learn about.
The scientific uncertainty has also widened. A 2024 study3 reported evidence of so-called ‘dark oxygen’ production on the abyssal seafloor (that is, oxygen generated without sunlight). This is a finding that, if confirmed, could challenge our existing assumptions about deep-ocean chemistry and the environmental baselines that are used in impact assessments.
As a result, the argument over deep-sea mining now sits at the intersection of environmental risk, scientific uncertainty, industrial strategy and geopolitical competition, with no clear consensus yet on how those priorities should be balanced.
The US executive order4 streamlining permitting for deep-sea mining exploration is grounded on the logic that polymetallic nodules (and other potential deep-sea resources) represent a significant non-Chinese source of critical minerals. Securing that supply chain, particularly for minerals essential to battery and defence applications, has become a priority in Washington.
China’s role adds another layer to the discussion. While often less visible in the public debate, Chinese entities hold multiple exploration licences through the International Seabed Authority. Some discussions have highlighted that the ISA’s requirement for multi-year commercial-scale testing may favour state-backed operators capable of absorbing these potentially lengthy pre-revenue phases. This provides a totally different risk profile when compared to privately financed Western ventures, such as The Metals Company (with $100s of million invested and no state equity behind it).
The Question That No One Can Quite Answer
“Science must guide decision-making” is a phrase that surfaces repeatedly in deep-sea mining discussions, offered by proponents and opponents alike. The difficulty is that the science is incomplete. Whilst research has developed hugely over the last few decades, we still understand the abyssal environment poorly. Environmental assessments for commercial-scale extraction are being developed in parallel with the operations they are designed to evaluate.
The question is not simply whether deep-sea mining causes harm – it does. The question is whether that harm is permissible relative to the alternatives: terrestrial mining with its own considerable footprint, or a geopolitical landscape in which critical mineral supply chains remain concentrated in a single country.
As one speaker framed it during discussions I was in attendance of this month:
“Do metals help progress humanity? Yes. Do we need them from the seabed? That depends entirely on what you prioritise.”
The ISA negotiations in Kingston this week will not resolve that question. But they may determine whether there is still a multilateral framework capable of asking it.
– Jocelyn Barker, Sustainability Consultant at Satarla
Want To Find Out More?
Deep sea mining sits at the intersection of climate ambition, resource demand, and environmental risk. One of the most valuable ways to navigate that complexity is by engaging with platforms designed to bring different perspectives together.
- Responsible Raw Materials is a non-profit initiative works to foster open, informed dialogue on how raw materials are sourced, used, and governed. Rather than advocating a single viewpoint, it brings together voices from across industry, policy, academia, and civil society to explore what “responsible” really means in practice. It also curates a growing library of talks, learning materials, and expert insights to help make sense of complex issues like deep sea mining.
- Join The Conversation: Each year, Responsible Raw Materials hosts a free, online global conference, open to anyone interested in the future of mineral supply chains. This year’s conference, titled ‘Creating Certainty in a World of Change‘ is open for registration now.
- Join The Conversation: Each year, Responsible Raw Materials hosts a free, online global conference, open to anyone interested in the future of mineral supply chains. This year’s conference, titled ‘Creating Certainty in a World of Change‘ is open for registration now.
- Watch this Critical Productions video with Prof. Sarah Gordon, CEO of Satarla, as she discussed Deep Sea Mining with Professor Richard Herrington of London’s Natural History Museum. Watch as he dives into the issues around deep sea mining & the origins of oceanographic science. View the video here.
Article Sources
- https://www.mining.com/deep-sea-mining-debate-reaches-critical-global-moment/ ↩︎
- https://investors.metals.co/news-releases/news-release-details/noaa-determines-tmc-usas-consolidated-deep-seabed-mining ↩︎
- https://www.nature.com/articles/s41561-024-01480-8 ↩︎
- https://www.whitehouse.gov/presidential-actions/2025/04/unleashing-americas-offshore-critical-minerals-and-resources/ ↩︎