ORRAA Policy Brief: Deep Seabed Mining
Every time scientists explore the deep seabed, new species of animals and microbes are revealed. Their connections to the life in the water column above them remain a mystery. Knowledge about the quantity of carbon sequestered in the seabed has not yet been calculated. Less than a year ago, a profound discovery was announced: the deep sea is the second source of oxygen production, challenging the consensus that it is only produced through photosynthesis. The discovery of “Dark Oxygen” -oxygen produced in complete darkness on the deep ocean floor- is one more example of how limited our understanding of the deep sea is. We know more about the surface of the Moon than we do about the deep seabed.
At the same time, interest in deep-seabed mining (DSM) has grown in recent decades, driven by a growing understanding of the distribution of seafloor mineral deposits, technological advancements that make exploration and exploitation more feasible, as well as increasing demand for metals.
Proponents of DSM aim to extract these deposits from the seafloor through large-scale industrial mining activity operating at depths ranging from 200 to 6,500 meters. Yet the scope of potential impacts, and the risks that such large-scale industrial extraction poses to these fragile habitats and the biodiversity in the water column above them, remain unknown.
Why is this important?
The vast majority of deep-sea marine scientists, and a growing list of 33 countries (as of May 2025), from Palau to France, are advocating for a DSM moratorium, a precautionary pause, or an outright ban. Given the scientific unknowns, and potential collateral damage from opening the deep seabed to massive industrial extraction, as well as emerging climate, ocean and human rights risks, these countries argue for the application of a highly precautionary way forward.
DSM will likely face significant challenges, including technological failure, unforeseen expenditures, environmental risks, and costly litigation battles. The potential release of sequestered carbon and compounding already-existing threats to marine biodiversity from ocean heating, pollution and acidification, make DSM not environmentally or economically defensible.
In addition to these clear risks from DSM, a precautionary approach also presents opportunities. Pausing DSM could support stronger ocean governance, particularly of the high-seas. It could also help prioritise deep-sea research and support the development of partnerships on capacity building and technology transfer. Ultimately, a pause will strengthen the Ocean as living capital. By investing in its sustainability, we invest in our own health and the shift towards a regenerative and sustainable blue economy.
Growing opposition
A 2022 report by the UN Environment Programme Finance Initiative states that “in their current form, there is no foreseeable way in which the financing of deep-sea mining activities can be viewed as consistent with the Sustainable Blue Economy Finance Principles”. The report provides a detailed overview of the possible reputational, regulatory and operational risks associated with DSM and outlines how financial institutions should focus on alternative strategies such as reducing the environmental footprint of terrestrial mining and supporting a transition to a circular economy.
The International Capital Market Association and the International Finance Corporation echoed this in their Blue Bond Guidance, stating that investments in “non-renewable extractive industries (e.g. offshore oil and gas, dredging, and deep-sea mining) are therefore excluded” from the definition of the Sustainable Blue Economy in supporting the issuance of credible blue bonds.
Recommendations
ORRAA echoes the concerns of a growing number of financial institutions, businesses, governments, scientists, and civil society with regard to the lack of a full understanding of the environmental, social and economic risks of DSM. ORRAA is also concerned that robust regulatory frameworks are not in place to enable the International Seabed Authority to manage this activity in a transparent, accountable, inclusive, and environmentally responsible manner. As such, ORRAA recommends:
- Governments: Support a precautionary pause on DSM until at least 2030 in ‘the Area’ (the seabed in areas beyond national jurisdictions); and not allow DSM within their jurisdictions.
- Private sector: Financial institutions to develop policies to exclude financing or investing in companies involved in DSM, and other businesses to develop procurement policies that exclude deep-sea minerals from their supply chains. Additionally, we recommend signing up to the Statement Supporting a Moratorium on Deep Sea Mining led by ORRAA member WWF.
To read the full ORRAA Policy Brief on Deep Seabed Mining, please click here.