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Drill, Baby, Drill: An environmentalist case for deep sea mining

Unlikely as it may seem in our current moment of political paralysis, consider the following thought experiment: A rare tide of reason sweeps across the United Nations at next year’s Convention on Climate Change’s Conference of the Parties. Delegates from every member state sign legally binding commitments to rapidly reduce annual global carbon dioxide (CO2) emissions from their current level of 35 gigatons to below five gigatons by 2050. The existential task of keeping global temperature increases below 1.5 degrees Celsius suddenly appears within reach. Greta Thunberg becomes Secretary General. Saudi Aramco, ExxonMobil, and Gazprom sign a moratorium on all fossil fuel production. Tesla stock soars again.

Still, this decarbonization fantasy fails to address a critical problem. If we were to continue procuring base metals for batteries the way we currently do, we would effectively just shift the environmental and social cost of fossil fuel extraction to the mining industry. What’s the alternative? Enter deep-sea polymetallic nodules: potato-sized mineral formations found in concentrated deposits across the ocean floor. They contain all the nickel, cobalt, manganese, and other base metals needed to power a global fleet of electric vehicles several times over, at a fraction of the ecological cost of terrestrial mining. If we are to have any shot at electrifying the transportation industry in a socially just and sustainable way, we must rapidly mobilize the political will and capital needed to scale the supply chain for mining deep-sea nodules.

To put things in perspective, there are currently 1.3 billion passenger vehicles on the road. Together, they contribute to about 15 percent of global greenhouse gas emissions. To replace all one billion gas-fueled engines with electric vehicles, each fitted with a standard 75 kWh battery, we would need 85 million tons of copper, 56 million tons of nickel, seven million tons of manganese, and seven million tons of cobalt. Given the trend towards electrification, the World Bank forecasts that the demand for nickel, manganese, lithium, cobalt, and aluminum will increase by greater than 1,000 percent in the coming decades.

While we should applaud—even accelerate—the shift towards electric vehicles, we should also be very concerned with how we currently obtain all that metal. Ideally, car manufacturers would procure the necessary base metals by simply recycling what has already been extracted, since 95 to 99 percent of the metals used in electric vehicle batteries are recyclable. Doing so would vastly reduce the energy requirements of battery production, decreasing CO2 emissions, toxicity, acidification, and other environmental indicators by 70 to 95 percent. Unfortunately, experts estimate that even in the highly idealistic case in which we achieve a 100 percent recycle rate in our supply chains, we would still need anywhere from 3 to 10 times more base metals than are currently in circulation to meet the future demand from car manufacturers alone. It’s no wonder that during Tesla’s quarter three earnings call for the fiscal year 2020, CEO Elon Musk pleaded to “any mining companies out there, please mine more nickel… efficiently and in an environmentally friendly way.” If only it were so easy.

Extracting all of the base metals needed to power one billion electric vehicles via today’s terrestrial mining processes would spell unquestionable disaster for our planetary ecosystem. Doing so would generate 350 billion tons of waste, leak toxic elements into our food and water supplies, emit 1.45 gigatons of CO2 into the atmosphere, clear 156,000 kilometers of land, and endanger 568 million tons of biomass. For comparison, the entire human species comprises only about 100 million tons of biomass.

There are also profound humanitarian risks associated with procuring base metals through terrestrial mining processes. These risks made headlines in September of 2020 when Rio Tinto, the second-largest mining conglomerate in the world, demolished a 46,000-year-old sacred aboriginal site in Australia. This wasn’t an iso- lated event; exploitative land and labor practices run deep in the metal mining industry. Cobalt extraction, 60 percent of which takes place in the Democratic Republic of the Congo, is an industry rife with child labor abuses. In Brazil, federal prosecutors are still seeking $27 billion in damages from BHP and Vale, two of the world’s largest min- ing companies, after the 2015 collapse of one of their mining sites left 19 dead and contaminated rural water reservoirs. Vale is also liable for the 2019 Brumadinho Dam collapse, which killed 270 people, despite management’s knowledge of structural integrity issues at the dam. Nonetheless, such checkered humanitarian track records have not deterred Tesla executives from meeting with both BHP and Vale to discuss potential nickel supply contracts. Other car companies adding to their lineup of electric vehicles—such as Volkswagen and BMW—are likely to follow suit.

Fortunately, deep-sea polymetallic nodules have the potential to save us from such an utterly irresponsible and unsustainable supply chain. While only one percent of extracted terrestrial ores can be used to supply base metals, the rest being wasted, nearly 100 percent of a polymetallic nodule is composed of usable material. Compared to terrestrial mining, deep-sea mining produces 75 percent less carbon and releases 99 percent less toxic waste. Moreover, deep sea-mining comes with little to no risk of endangering forests, Indigenous communities, or freshwater reserves.

If any one company is best positioned to supply the world’s demand for battery base metals via sea floor nodules, it’s DeepGreen. Founded in 2011, the Canadian start-up has received 30-year licenses from the International Seabed Authority (ISA) to explore deposits located 3,800 to 5,500 meters below the Clarion Clipperton Zone (CCZ) in the South Pacific Ocean.

The CCZ is officially designated as international waters and is therefore included in the “common heritage of mankind,” as per the United Nations Convention for the Law of the Sea. As a result, international law demands that any commercial activities taking place in their vicinity be sponsored by a UN designated Small Island Developing State and spur sustainable economic development for said state’s citizens. So far, the island nations of Nauru, Kiribati, and Tonga have all sponsored DeepGreen’s mining permits in the CCZ. International law also requires contractors to conduct environmental impact assessments with respect to their future mining operations, something DeepGreen is in the process of doing. Meanwhile, the ISA is finalizing a regulatory framework that, if completed by the end of 2020 as expected, would promptly permit commercial scale mining activities to commence.

However, not everybody is rooting for team DeepGreen. In 2019, Greenpeace, a reputable conservation nongovernmental organization, advocated for an immediate moratorium on all deep-sea mining. Some environmental activists are concerned about the potential impact that mining could have on deep-sea marine life. Specifically, they worry that massive sediment plumes created by mining equipment may result in habitat loss, putting the many corals, sponges, and other filter feeders that inhabit the ocean floors at risk of extinction.

Greenpeace and others’ objections miss the bigger picture. Greenpeace’s mission statement includes a commitment to “promote solutions that are essential to a green and peaceful future.” Yes, we should be concerned about the potential impact that sea floor mining could have on deep sea marine life. But, as the UN Intergovernmental Panel on Climate Change’s annual report argues, the electrification of our transportation system is an indispensable part of any plan to limit warming to 1.5 degrees Celsius. There are two ways to do this: by extracting base metals in the same, irresponsible way that we have been for decades past, or by sourcing them using polymetallic nodules. And we know that the latter option exacts an incomparably smaller toll on our atmosphere, our biodiversity, and the safety of Indigenous and historically marginalized communities. The costs of inaction—mass human displacement, heat waves, forest fires, crop failures, droughts, flooding, and hurricanes, all with greater frequency and intensity—are existential threats far too great to ignore.