01-22 deep sea mining

[Image above] An animated representation of deep sea mining. Such mining could be the key to securing a steady source of critical materials—but it could cost the marine environment dearly. Credit: Massachusetts Institute of Technology (MIT), YouTube

As renewable energy technologies and electric vehicle adoption continue to expand rapidly, the global batteries market expands rapidly as well.

Batteries are the linchpin of both markets—they store electricity generated by renewable energy and release electricity to power electric vehicles. However, many current battery technologies require critical materials to work, notably cobalt.

Almost two-thirds of the world’s cobalt comes from the Democratic Republic of the Congo. But recently the cobalt mining industry there has come under increased scrutiny for use of child labor, and now some big name tech companies including Apple and Google are facing a lawsuit for their supposed complicity in aiding and abetting this practice.

For battery manufacturers, obtaining cobalt and other critical materials is a necessity if they wish to keep pace with the growing demand for batteries. But obtaining these materials while respecting labor and environmental regulations has driven some manufacturers to explore some previously unfathomable locations.

One such place is space. As we discussed in a CTT post published earlier this month, a whole slate of startup companies are raising millions of dollars in funding to support lunar mining expeditions.

Not all moonshot mining expeditions are literally going to the moon, however. Some expeditions’ aims are more “watered” down—to mine the bottom of the ocean.

Deep sea mining refers to mineral retrieval processes that take place on the ocean floor. The term is generally applied to extraction of three distinct types of ore deposits found in the deep sea:

  • Seafloor massive sulfides (hydrothermal vents)
  • Ferromanganese (polymetallic) nodules
  • Cobalt crusts

Of these three, most deep sea mining research and exploration focuses on the first two.

Illustration of the deep sea mining process for polymetallic nodules. Credit: MimiDeepSea, Wikimedia (CC BY-SA 4.0)

Interest in deep sea mining initially picked up in the 1960s with the publication of a 1965 book that claimed nearly limitless supplies of critical materials could be found throughout the planet’s oceans. The possibility was explored and then abandoned by the 1980s, but interest in the topic has grown again in the 2000s—and now is poised to become a serious venture.

“In 2018, [De Beers Group] ships extracted 1.4 million carats [of diamonds] from the coastal waters of Namibia; in 2019, De Beers commissioned a new ship that will scrape the bottom twice as quickly as any other vessel,” according to an article from The Atlantic on the consequences of deep sea mining. “Another company, Nautilus Minerals, is working in the territorial waters of Papua New Guinea to shatter a field of underwater hot springs lined with precious metals, while Japan and South Korea have embarked on national projects to exploit their own offshore deposits.”

All these underwater mining programs currently take place just offshore or in waters designated as a country’s national territory. Mining in international waters—waters that transcend national boundaries—is not allowed.

However, that could soon change. The International Seabed Authority (ISA), an autonomous international organization established by the United Nations to govern resources of the deep seabed, has granted “exploratory” permits around the world in international waters and is writing an underwater Mining Code to regulate commercial mining. The Atlantic article reports that officials hope the code will be ratified for implementation this year.

With commercial deep sea mining so close to becoming reality, people may assume that scientists know what the environmental impact of such mining would be and how to limit it. Unfortunately, that is far from the case.

Until recently, it was assumed the deep sea hosted minimal life because the traditional model of life relies on photosynthesis (energy derived from sunlight). But when a pair of oceanographers discovered an intricate web of life around hydrothermal vents in 1977, marine biologists realized chemosynthesis (energy derived from chemical reactions) could also support life and began to realize the deep sea is actually incredibly diverse.

To date, knowledge of deep sea ecosystems is limited, and knowledge of the environmental impacts of deep sea mining is even scarcer. Thus, researchers are strongly cautioning mining companies from pursuing deep sea mining too quickly when so much is still unknown.

One aspect of deep sea mining in particular that worries marine biologists is sediment plumes, i.e., collections of sand, dirt, and rocks stirred up when mining technologies dredge the ocean floor. It is unknown how far plumes can travel or their effects on the marine environment.

Many research groups are investigating these plumes, including a team from the Massachusetts Institute of Technology. In today’s video, the MIT team talks about their research on tracking plumes thousands of feet below the water’s surface.

So, should we mine the deep sea? There are many different answers to that question, but one thing is for sure—we are now able to answer that question with more confidence.

In July 2019, the ISA launched its newly developed ISA Deep Data repository, which holds centralized data of public and private information on marine mineral resources acquired from various institutions worldwide. A National Geographic article from last year explains this database, which contains all environmental data reported by miners since 2001, is the first time “scientists will be able to analyze the quantity and quality of that information and determine if mining contractors have complied with ISA rules.”

Credit: Massachusetts Institute of Technology (MIT), YouTube