Deep-sea mining has become a focal point of a debate on whether or not it should take place, as governments, mining companies, and environmentalists grapple with a fundamental question.
Can the minerals necessary to build a lower carbon future be sourced from the ocean floor without compromising the health of the world’s largest and most important ecosystem?
“While commercial interest is accelerating, many of the questions around long-term ecosystem impacts remain unanswered,” Ilya Epikhin, principal at Arthur D. Little says to Mining.com.au.
Deep-sea mining is the process of extracting mineral deposits from the ocean floor, typically at depths greater than 200m. Materials extracted from the ocean floor are considered essential building blocks for electric vehicle batteries, wind turbines, and solar panels.
Mining the deep sea has several different environmental impacts that remain uncertain. Some of these can lead to ecosystem effects including biodiversity loss, as well as possibly affect ecosystem services provided to humans.
The National Oceanography Centre (NOC) reports that exploring the ocean requires a deep understanding of marine geology, ecology, climate science, and international law.
Currently, no country has fully operational commercial deep-sea mining, but exploration licences have been issued globally.
The Pacific Ocean, particularly around the Clarion-Clipperton Zone between Hawaii and Mexico, is the most targeted region. This is due to hosting nodules, which have an estimated value of between US$8—20 trillion ($11.36—28.41 trillion).
As Mining.com.au reported earlier this year, there is a possibility for deep-sea mining to ramp up between late 2026 and early 2027.
This news follows the National Oceanic and Atmospheric Administration (NOAA) finalising a new rule under the Deep Seabed Hard Mineral Resources Act, which modernises and streamlines the permitting process for US entities.
Exploring the ocean
As today marks World Oceans Day (8 June), companies looking to pursue seabed mining are showing true water stewardship approaches.
“A true water stewardship approach is a must have to meet both stakeholder and environmental commitments, and in water-scarce regions,” Epikhin explains.
“Getting this wrong doesn’t just damage ecosystems, it ruins the social licence to operate entirely.”
NOC has been leading research expeditions to all major types of areas being considered for deep-sea mining, including nodule fields, seamounts, and hydrothermal vents.
On these trips, NOC combines geological sampling, environmental monitoring, and biological surveys to build a picture of remote ecosystems and what could happen if they are disturbed.
NOC’s current projects include SMARTEX, ULTRA, and TRIDENT.
SMARTEX aims to better understand the ecosystem in the Pacific abyss and how the different components interact and interconnect. NOC is assessing water and its dynamic flows over time and space, monitoring the area for a year to capture its variabilities, particularly storm events near the seabed.
Once completed, NOC will predict where the sediment plume generated by mining will be transported and settle back to the seafloor. It will then assess the linkages between the water and sediment surface and sub sediments, evaluating the natural cycling of nutrients and metals that is important to maintain ecosystem health.
ULTRA aims to test the hypothesis that ultramafic-hosted seafloor massive sulphides (muSMS) deposits form extensive sub-surface mineralisation and undergo post-formational modification at and beneath the seafloor under the influence of highly variable pH conditions.
MuSMS form some of the largest deposits known, hosting high metal concentrations of gold, copper, nickel, cobalt, and platinum.
NOC intends to combine electromagnetic induction and inverted down-hole seismic tomography with surface mapping and sub-seafloor drilling to image the 3D structure and composition of the deposit and its surroundings.
Companies making it possible
Other companies working to deliver mining solutions for deep-sea mining include Impossible Metals, which completed a proof of concept trial for its first autonomous underwater vehicle (AUV) — Eureka I — in December 2022.
The technology involves artificial intelligence (AI)-guided selective picking and extraction of nodules.
Meanwhile, Deep Sea Minerals (CSE:SEAS) recently received confirmation from the NOAA that its application under the Deep Seabed Hard Minerals Resource Act is in substantial compliance with regulatory requirements.
Upon full application approval, the company’s seabed mineral concession spans 150,000km2 within the Pacific Ocean across offshore exploration blocks defined by geographic coordinates under NOAA’s act framework.
CEO James Deckelman says this approval reinforces the company’s commitment to advancing responsible, science-based development of critical mineral resources.
“We believe the US is increasingly recognising the strategic importance of secure and diversified critical mineral supply chains, and we are proud to be participating in that emerging framework,” Deckelman says.
Under-water challenges
Epikhin says one of the biggest challenges for the mining industry is balancing resource development with long-term ocean and environmental sustainability.
“Ecological systems damaged today may not recover on any human timescale, and the regulatory frameworks are moving faster than the environmental science,” Epikhin says.
Another challenge is to govern the ungoverned frontier, which Epikhin describes as “very complex”.
“The opportunity is that mining stays at the centre of the energy transition, which gives the industry a real chance to demand better standards across supply chains and set a new kind of base about what responsible extraction actually looks like,” he tells this news service.
As reported in recognition of World Environment Day (5 June), the industry sits at the centre of a complex but unavoidable equation. Mining is being called upon to supply critical minerals needed to power electrification and renewable energy systems, while reducing the environmental footprint of extracting them.
According to EY, around 115% of additional copper needs to be mined over the next 30 years to meet the world’s electrification goals.
Copper is a highly efficient conduit, used in renewable energy systems to generate power from solar, hydro, thermal, and wind energy. Renewable energy sources provide nearly a quarter of the world’s power, and copper plays a key role in making power generation as efficient as possible.
When it comes to land-based operations, Epikhin says there is “genuine” progress.
“But the bigger story right now is deep-sea mining, where the industry is moving faster than science,” he says.
“Critical sustainability paradox: we need the minerals, yet hard to prove you have a sustainable way to extract them… The scale and reversibility of environmental impacts remain unsolved, yet permitting is being accelerated anyway.“
“That’s a concern. But on the other side, both Amer [Hage Chahine] and I did huge research on this topic and actually the vast majority of money spent on seabed exploration is spent on the environmental impact assessment topic.”
Epikhin adds that despite the arguments being made regarding deep-sea mining, companies and people are showing care for the environment.
Deep possibilities
With only about 20% of the Earth’s ocean actually being explored, leaving a significant 80% largely known, it is plausible to say that there is an immense amount of resources in the ocean.
According to estimates by The Perth Mint, around 20 million pounds of gold is believed to be at the bottom of the ocean floor.
The Australasian Historical Archaeology reports that in 1866, scientists had suggested that the ocean may contain more than 250 million times more gold than the total present wealth of mankind in the precious metal.
As previously reported, gold finds its way into the ocean through natural erosion of rocks on land, carried by rivers and streams into the sea.
With commercial activities edging closer, the future of deep-sea mining ultimately depends not on whether resources exist, but on whether governments, industry, and researchers can demonstrate that they can be extracted responsibly.
Until then, the ocean floor remains a source of immense opportunity and one of the mining sector’s greatest environmental tests.
Write to Aaliyah Rogan at Mining.com.au
Images: Mining.com.au, Deep Sea Minerals, NOAA & Nautilus Minerals
