The jets propelled the lumpy stones into an intake at the front of the vehicle, where they rattled into a steel pipe rising all the way back up to the ship. Air compressors pushed the rocks up in a column of seawater and sediment and into a shipboard centrifuge that spun away most of the water. Conveyor belts then carried the rocks to a metal ramp that dropped them with a clatter into the ship’s hold. From a windowless control room nearby, a team of engineers in blue and orange coveralls monitored the operation, their faces lit by the polychromatic glow from a hodgepodge of screens.

The ship, called the Hidden Gem, was a former oil-drilling vessel nearly 800 feet long, retrofitted for sea mining by the Metals Company, an international firm officially headquartered in Canada. This was the first test of its system to collect the ancient black stones. They are officially known as polymetallic nodules, but the Metals Company’s CEO, Gerard Barron, likes to call them “batteries in a rock.” That’s because the stones happen to be packed with metals that are essential for manufacturing electric cars—a market that is surging worldwide. Barron’s company is at the front of a pack of more than a dozen enterprises slavering over the billions of dollars that could be reaped from those little subsea rocks.

The world’s long-overdue, fitful transition to renewable energy is hobbled by an Achilles’ heel: It requires staggering quantities of natural resources. Manufacturing enough electric vehicles to replace their fossil-fueled counterparts will require billions of tons of cobalt, lithium, copper, and other metals. To meet the exploding demand, mining companies, carmakers, and governments are scouring the planet for potential mines or expanding existing ones, from the deserts of Chile to the rain forests of Indonesia. Meanwhile, what might be the richest source of all—the ocean floor—remains untapped. The US Geological Survey estimates that 21 billion tons of polymetallic nodules lie in a single region of the Pacific, containing more of some metals (such as nickel and cobalt) than can be found in all the world’s dryland deposits.

“Here’s one of them,” Barron said when we met recently in the lobby of a chic Toronto hotel, as he casually pulled one of these geologic oddities out of his jacket pocket and handed it to me. Barron is a fit, muscular Australian in his mid-fifties, with swept-back dark hair, a nautical beard, and craggy Kurt Russell-esque looks. His jeans, black boots, and wristloads of leather bracelets lend him a roguish air. He has just flown in from London for a big mining conference. For years, he’s been traveling the world to talk up deep-sea mining to investors and government officials. He and other would-be sea miners argue that collecting nodules from the deep will be not only cheaper than traditional mining but also gentler on the planet. No rain forests uprooted, no Indigenous peoples displaced, no toxic tailings poisoning rivers.

Barron may finally be on the brink of achieving his goal of mega-scale mining on the ocean floor. The Metals Company has tens of millions of dollars in the bank and partnerships with major maritime companies. The Hidden Gem’s foray last October marked the first time since the 1970s that any company had successfully trialed a complete system for harvesting nodules.

The main thing holding the company back is international law, which currently forbids deep-ocean mining. That may be about to change, however. Last year, the Metals Company teamed up with the tiny South Pacific island nation of Nauru to trigger an obscure process that could let them bypass the international prohibition and get a license to start full-scale operations as early as July 2024.

That prospect has sparked an outraged backlash. Environmental groups, scientists, and even some corporations in the market for battery metals fear the potential havoc of seabed mining. The oceans provide much of the world’s biodiversity, a significant chunk of humanity’s food, and the planet’s biggest carbon sink. No one knows how such an unprecedented incursion would affect the many life-forms that live in the abyssal depths, the marine life farther up the water column, or the ocean itself. The European Parliament and countries including Germany, Chile, Spain, and several Pacific island nations have joined dozens of organizations in calling for at least a temporary moratorium on deep-sea mining. Several banks have declared they won’t loan to ocean-mining ventures. Corporations including BMW, Microsoft, Google, Volvo, and Volkswagen have pledged not to buy deep-sea metals until the environmental impacts are better understood. Even Aquaman is opposed: Jason Momoa narrated a recently released documentary denouncing sea mining.

“This has the potential to transform the oceans, and not for the better,” says Diva Amon, a marine scientist who has worked extensively in the main area of the Pacific targeted for mining, including as a contractor for one of the sea-mining companies. “We could stand to lose parts of the planet and species that live there before we know, understand, and value them.”

None of that deters Barron. “The biggest challenge to our planet is climate change and biodiversity loss. We don’t have a spare decade to sit around,” he declares. By the end of the Hidden Gem’s trial last October, the vehicle had delivered more than 3,000 tons of the stones, mounded up in a glistening black pyramid nearly four stories high. “This,” Barron promised the press, “is just the beginning.”

One March day in 1873, some of these subaqueous artifacts were dragged for the first time into sunlight. Sailors aboard the HMS Challenger, a former British warship retrofitted into a floating research lab, dredged a net along the sea bottom, hauled it up, and dumped the dripping sediment onto the wooden deck. As the expedition’s scientists, in long trousers and shirtsleeves, eagerly sifted through the mud and muck, they noted the many “peculiar black oval bodies” that they soon determined were concretions of valuable minerals. A fascinating discovery, but it would be almost a century before the world began to dream of exploiting these stones.

In 1965, an American geologist published an influential book called The Mineral Resources of the Sea, which generously estimated that the nodules contained enough manganese, cobalt, nickel, and other metals to feed the world’s industrial needs for thousands of years. Mining the nodules, he speculated, “could serve to remove one of the historic causes of war between nations, supplies of raw materials for expanding populations. Of course it might produce the opposite effect also, that of fomenting inane squabbles over who owns which areas of the ocean floor.”

In an era when population growth and an embryonic environmental movement were fueling concerns about natural resources, seabed mining suddenly got hot. Throughout the 1970s, governments and private companies rushed to develop ships and rigs to pull up nodules. There was so much hype that in 1972, it seemed completely plausible when billionaire Howard Hughes announced that he was dispatching a custom-built ship into the Pacific to search for nodules. (In fact, the CIA had recruited Hughes to provide cover for the ship’s Bond-esque mission: to covertly retrieve a sunken Soviet submarine.) But none of the actual sea miners managed to come up with a system that could do the job at a price that made sense, and the fizz went out of the nascent industry.

By the turn of the 21st century, advancing marine technology made sea mining seem plausible again. With GPS and sophisticated motors, ships could float above precisely chosen points on the seafloor. Remotely operated underwater vehicles grew more capable and dove deeper. The nodules now seemed to be within reach, just at the moment when booming economies such as China’s were ravenous for metals.

Barron saw the potential bonanza decades ago. He grew up on a dairy farm, the youngest of five kids. (He now has five of his own.) “I knew I didn’t want to be a dairy farmer, but I loved dairy farm life,” he says. “I loved driving tractors and harvesters.” He left home to go to a regional university and started his first company, a loan-refinancing operation, while still a student. After graduating, he moved to Brisbane “to discover the big, wide world.” Over the years, he has been involved in magazine publishing, ad software, and conventional car battery operations in China.

In 2001, a tennis buddy of Barron’s—a geologist, former prospector, and early web-hosting entrepreneur named David Heydon—pitched him on a company he was spinning up, a sea-mining outfit called Nautilus Minerals. Barron was fascinated to learn that the oceans were filled with metals. He put some of his own money into the venture and rounded up other investors.

Nautilus wasn’t going after polymetallic nodules, but rather what seemed like an easier target: underwater formations called seafloor massive sulfides, which are rich in copper and other metals. The company struck a deal with the government of Papua New Guinea to mine sulfides off the country’s coast. (Under international law, countries can do basically whatever they want within their Economic Exclusion Zones, which extend up to 200 miles from their coastlines.) It sounded good enough to attract half a billion dollars from investors, including Papua New Guinea itself.

But in 2019, after spending some $460 million, Nautilus went bust. Neither Barron nor Heydon lost any of their own money: Both had sold their shares about a decade earlier, with Barron clearing about $30 million in profit. Papua New Guinea, where more than half the population lives in poverty, was out $120 million. “It wasn’t my business,” Barron tells me. “I was just supporting David, really.”

Heydon, meanwhile, was building a company called DeepGreen—rebranded in 2021 as the Metals Company—this time pursuing polymetallic nodules. By then, the growing demand for electric vehicles had added both a new potential market and an extra environmental justification for the project. Barron came on as CEO, and several other Nautilus alums joined up, including Heydon’s son Robert. Along with other would-be miners, they started knocking on the door of the International Seabed Authority.

Based in Kingston, Jamaica, the ISA has the contradictory tasks of protecting the ocean floor while organizing its commercial exploitation. Back in the 1980s, most of the world’s nations—notably excluding the United States—signed a kind of constitution for the oceans, the United Nations Convention on the Law of the Sea. Among many other things, the document established the International Seabed Authority to represent what are now its 167 member nations. The organization was charged with devising rules to govern the then-nonexistent deep-sea-mining industry. The testudinal pace of subsea geology is rivaled only by that of international bureaucracy, and the ISA has been working to develop those rules ever since. Until regulations are agreed upon, full-scale mining is prohibited. But in the meantime, the agency can grant miners the rights to explore specific areas and reserve them for commercial exploitation. The ISA also declared that private companies must partner with a member country. Even the tiniest member country will do.

By now, the Seabed Authority has granted permits to 22 companies and governments to explore enormous swaths of the Pacific, Atlantic, and Indian Ocean seabeds. Most are targeting nodules lying roughly 3 miles underwater in the Clarion Clipperton Zone, an expanse of the Pacific between Mexico and Hawaii measuring 1.7 million square miles. Holding the rights to three of the choicest parcels is Gerard Barron and the Metals Company. The company’s chief financial officer recently told investors that those expanses could yield metals worth $31 billion.

Here’s what makes all of this urgent. The mining ban has a loophole: the two-year trigger. A section of the treaty known as Paragraph 15 states that if any member country formally notifies the Seabed Authority that it wants to start sea mining in international waters, the organization will have two years to adopt full regulations. If it fails to do so, the treaty says the ISA “shall none the less consider and provisionally approve such plan of work.” This text is commonly interpreted to mean mining must be allowed to go ahead, even in the absence of full regulations. “Paragraph 15 was appallingly drafted,” says Duncan Currie, a lawyer for the Deep Sea Conservation Coalition, an international umbrella organization of dozens of groups. “Several countries dispute the idea that it means they need to automatically approve a plan of work.”

In the summer of 2021, the president of Nauru formally notified the Seabed Authority that the country, along with the Metals Company’s wholly owned subsidiary, Nauru Ocean Resources, planned to begin sea mining. The two-year trigger has been pulled. The Metals Company’s audacious gambit may have opened the door to deep-sea mining for the first time.

Very little is truly known about the deep ocean. Gathering data hundreds of miles from land and miles below the water’s surface is extraordinarily difficult. A single day’s work can cost up to $80,000, and sophisticated tools such as remotely operated vehicles have only recently become available to many scientists. In 2022, 31 marine researchers published a paper that reviewed hundreds of studies on deep-sea mining. The authors also interviewed 20 scientists, industry members, and policy-makers; almost all said the scientific community needed at least five more years “to make evidence-based recommendations” for regulating the industry.

Every phase of the mining process entails serious risks for the world’s oceans, which are already severely stressed by pollution, overfishing, and climate change. Start at the bottom. A massive piece of machinery-tank-treading over the pristine ocean floor, prying loose thousands of nodules from the beds where they have lain for millennia, is inevitably going to cause some damage. Corals, sponges, nematodes, and dozens of other organisms live on the nodules themselves or shelter beneath them. Other critters float around them, including anemones with 8-foot tentacles, rippling squidworms, glass sponges, and ghostly white Dumbo octopuses. “It’s like Dr. Seuss down there,” says Amon, the marine scientist. The nodules, Amon believes, are a critical part of the ecosystem that supports all those creatures. And since they formed over millions of years, any harm that results from removing them “is in effect irreversible.” Some scientists are also concerned that the huge amounts of carbon embedded on the ocean floor could be released, potentially interfering with the ocean’s ability to sequester carbon.

Silt and clay stirred up by the collector vehicles will also rise up into the water, creating plumes of sediment that could cloud the water for miles, linger for weeks or more, and suffocate creatures farther up the water column. Those plumes might also contain dissolved metals or other toxic substances that could harm aquatic life.

Moving upward, the noise and light emitted by the harvester vehicles and riser systems could affect any number of creatures that have evolved to live in silence and darkness. A recent study found that the racket from just one seabed mining operation could echo for hundreds of miles through the water, potentially interfering with aquatic organisms’ ability to navigate and find food and mates.

Once the nodules have been carried up to a ship, the silt-infused water that accompanied them will have to be dumped back into the sea, creating another potentially dangerous sediment plume. “We are talking about massive volumes. Fifty thousand cubic meters a day,” says Jeff Drazen, an ocean scientist at the University of Hawaii who has also worked extensively in the Clarion Clipperton Zone, including on a research mission funded by the Metals Company. “That’s like a freight train of muddy seawater every day.”

A 2022 report from the United Nations Environment Programme sums up the grim picture. Bottom line, according to the authors: “Current scientific consensus suggests that deep-sea mining will be highly damaging to ocean ecosystems.” More than 700 marine science and policy experts have signed a petition calling for a “pause” on sea mining until more research has been conducted.

Barron insists that his company is committed to getting the science right and points out that it has funded 18 research expeditions (to fulfill the requirements of the Seabed Authority). “Last year I spent $50 million on ocean science,” he tells me. “I don’t see anyone else doing that.”

By now, he argues, we know enough. “The lack of full scientific knowledge should not be used as an excuse not to proceed when the known impacts of the alternative—land-based mining—are there for us all to see,” he says. It is a “certainty,” he says, that sea mining will be less destructive. Whoever authored the Metals Company’s own registration filing with the US Securities and Exchange Commission wasn’t so categorical. That document notes that nodule collection in the Clarion Clipperton Zone is “certain to disturb wildlife” and “may impact ecosystem function” to an unpredictable extent. The filing adds that it may “not be possible to definitively say” whether nodule collection will do more or less harm to global biodiversity than land-based mining.

The Metals Company’s critics say the company basically isn’t interested in what the science shows. One environmental scientist quit a contract job with the company, complaining in a since-deleted LinkedIn post in 2020 that “the company has minimal respect for science, marine conservation, or society in general … Don’t let them fool you. Money is the game. It’s business in their eyes, not people or the planet.” (Barron says this person is just a disgruntled ex-employee and that his charges aren’t true. My efforts to contact the scientist were unsuccessful.)

You’d have a hard time finding a more extreme example of despoliation of a tropical paradise, of a fall from Eden, than Nauru. When the first European ship came across this 8-square-mile island in the South Pacific, in 1798, the captain was so charmed by the locals’ friendly welcome, the fair weather, and the lovely beaches that he dubbed it Pleasant Island. But once an Australian geologist discovered that the spot was loaded with high-grade phosphate, much in demand as fertilizer, the outside world rushed in. Over the course of the 20th century, the nation of 12,000 people was strip-mined to the brink of oblivion. Its once-lush interior was reduced to what The Guardian described as a “moonscape of jagged limestone pinnacles unfit for agriculture or even building.” As the phosphate began running low in the 1990s, Nauru tried to set itself up as a no-questions-asked offshore banking haven, but so much ill-gotten cash poured in that Nauru was forced to tighten its regulations. The island’s next moneymaker was to rent some of its territory to Australia to use as an immigrant detention center. Detainees there have rioted, staged hunger strikes, and sewn their lips shut.

Given all that, it’s easy to see the economic appeal of teaming up with the Metals Company—especially since the mining zone is nowhere near Nauru. “Our people, land, and resources were exploited to fuel the industrial revolution elsewhere, and we are now expected to bear the brunt of the destructive consequences of that industrial revolution,” including sea-level rise, wrote Margo Deiye, Nauru’s representative to the UN, in a December newspaper op-ed explaining why her country is supporting sea mining. “We’re not sitting back, waiting for the rich world to fix what they created.”

Barron, who has never set foot on the island, insists that the relationship is a respectful partnership, not a modern version of colonial exploitation. “It’s horrible what happened to Nauru,” he says. “They were absolutely fucked over by the Germans, the English, the Australians, and the Kiwis.” The Metals Company says it has doled out more than $200,000 to support community programs of various sorts in Nauru, Kiribati, and Tonga, the two other island nations with which it has business arrangements. “The real contribution,” he adds, “will be when we start paying royalties”—the partner nations’ yet-to-be-decided percentage of mining revenues.

The Metals Company’s own finances, however, are a bit shaky. Barron took the company public in September 2021, a few months after the two-year rule was triggered, claiming it had commitments of $300 million from investors. Its stock topped $12 per share a few days after it hit the market. But two key investors never delivered, leaving Barron and his team with only a third of their expected capital. The stock price plummeted and has remained stuck at around $1 for months. The company is suing the faithless investors and is being sued itself by other investors who claim they were misled. Meanwhile, it has burned through $300 million. A substantial chunk of that cash wound up in Barron’s pocket. He and his partner, Erika Ilves, a former executive at a company aiming to mine water on the moon whom Barron brought on as chief strategy officer, were together paid more than $20 million in salary and stock options in 2021.

Bloomberg reporters and some environmental organizations have suggested that the company holds unfair leverage over its partner nations, and critics have drawn attention to the seemingly cozy ties between the Metals Company and the International Seabed Authority—in particular its secretary general, Michael Lodge. A recent New York Times investigation alleged that the ISA gave the company’s executives access to data indicating where the most valuable seabed tracts were located, then helped it secure the rights to those areas. Both the agency and the company say that all their dealings have been legal and appropriate. (Lodge also made his stance on environmentalists pretty clear, telling the Times: “Everybody in Brooklyn can say, ‘I don’t want to harm the ocean.’ But they sure want their Teslas.”)

Between Barron’s outspokenness and his company’s legal and financial pyrotechnics, the Metals Company has drawn most of the media coverage around sea mining. “TMC is very bold, but the other companies are piggybacking on them,” says Jessica Battle, who heads the World Wildlife Fund’s campaign against sea mining. “Once one mining license is given, others will follow.” There’s an eager lineup. Belgian maritime giant Deme, high-tech hardware colossus Lockheed Martin, ship-builder Keppel Offshore & Marine, and the governments of South Korea, India, Japan, Russia, and China have launched dozens of research expeditions in recent years. China has two outfits licensed to explore for polymetallic nodules in the Pacific.

Deme’s sea-mining subsidiary, Global Sea Mineral Resources, may be best positioned to take the lead if the Metals Company stumbles. “They’ve got the backing of a multibillion-dollar company and access to European resources for design,” says Currie, the environmental lawyer. “They can wait 10 or 15 years and it wouldn’t be the end of the world for them. Whereas with the Metals Company, look at their stock price. If their license isn’t approved, it’s hard to see how they survive.” Global Sea Mineral Resources has also been running extensive tests in the Pacific—and learning its own lessons in how badly things can go wrong.

It was, indeed, really bad. The umbilical is a Kevlar-jacketed cable stuffed with fiber-optic and copper wires. Nearly 3 miles long and as thick as a person’s arm, it was the only thing tethering the Patania to the ship.

“Is it going down?” De Bruyne called back.

“Yes!”

De Bruyne scrambled into his red coveralls and ran up on deck. The crew had been hauling up the vehicle after a test drive. When it was just 50 feet from the surface, the umbilical snapped. The 35-ton vehicle went spiraling back down to the bottom of the Pacific. De Bruyne stared helplessly over the side.

Luckily, the Patania landed with its locator system intact, sending acoustic pings up to the ship. It took a couple of days, but crew members eventually maneuvered down a small submersible robot equipped with three-fingered Doctor Octopus tentacles to reattach the repaired umbilical. “It was relatively easy. Well, I say it was very easy, but it was also like ‘AAAAHHH!’ and ‘NOOOO!’” De Bruyne recounted when I met him at Deme’s headquarters near Antwerp, Belgium. “It was an emotional roller coaster.”

When they hauled the Patania up, they found it almost completely undamaged. To De Bruyne, the snapped cable was just one of the “teething problems” that typically come with launching such a complex piece of equipment. Earlier in the expedition, he’d also had to contend with Greenpeace activists who had painted “RISK!” on his ship in huge yellow letters.

De Bruyne is fit, clean-shaven, and small in stature, with a fanboy’s enthusiasm for his job. He’s acutely conscious of the criticism directed at his industry, and he seems to take it personally. De Bruyne’s parents were traveling veterinarians, and they raised him and his brother in Rwanda and Vietnam. “I grew up in nature. I’m not the nature destroyer they want me to be,” he says. “The nongovernmental organizations and the environmentalists, they forget that we also have our stories and that we want to do something good for the world as well.”

The Patania mission, he points out, was accompanied by a separate boatload of independent marine scientists who monitored the machine’s impact on the ocean (as was the Metals Company’s foray). Still, the more we talked, the more qualms he confesses. “Once in a while, I’ll ask myself, am I still doing the right thing?” he says. “I still think we’re doing the right thing, because we’re still doing research.” He says he’s not even convinced deep-sea mining should go ahead. “We need to know what the impact would be of deep-sea mining, and I’m contributing to getting answers to that question. That’s how I feel about it.”

Global Sea Mineral Resources has already sunk at least $100 million into developing its subsea mining system, and it recently announced a partnership with Transocean, a major offshore oil-drilling outfit. The sea-mining company is now designing the much larger Patania III—the first of what the company hopes will be a fleet of full-scale mining robots that will hit the ocean floor around 2028.

The five years between now and then might be enough to develop the scientific understanding needed to craft regulations to safely mine the seafloor—or to determine whether it should be done at all. Or it might be time for alternatives, such as reducing private car ownership or recycling metals, to gain enough traction to make seabed mining superfluous. But frankly, none of these possibilities seem likely.

Gerard Barron is not planning to wait. “Got the boat, got the machine, announced the partnerships on how we’re going to process the nodules,” he says confidently. Assuming the Metals Company gets the go-ahead from the Seabed Authority, he says, everything is on track to start harvesting nodules by late 2024. The company’s goal for its first year is 1.3 million tons, scaling up to 10 times that amount in the next decade.

The two-year deadline expires this summer. After Nauru put the Seabed Authority on notice, the agency hurriedly convened several meetings, but results have been scant. The pressure seems to be generating something of a backlash. At the authority’s most recent meetings last November, several member states called for a “precautionary pause” on seabed mining, echoing the moratorium petition. According to Bloomberg, France’s representative declared that his country did not consider itself obligated to approve mining until it was satisfied with the regulations, and several other countries indicated they felt similarly. The UK, India, and Japan, however, want to try to hit the 2023 deadline. Some activists are even calling for the Seabed Authority to be overhauled or replaced.

“The general feeling is, there’s a lot of work to do and a lot of complex issues to be addressed. So when some country says, ‘Just gimme a contract, I’m gonna get on with it,’ it rankles enormously,” says Currie, who attended the most recent round of Seabed Authority meetings. There’s a widespread feeling that it is too soon to be giving out permission to start mining, he says, but it’s not clear how the organization might stop that from happening. “No one,” says Currie, “is sure how this will play out.” 

This story was supported by the  Pulitzer Center on Crisis Reporting. 

This article appears in the April 2023 issue. Subscribe now.

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