Will Deep-Sea Bed Mining Kill the Oceans?

At the bottom of the sea lies a treasure. Not one hidden by pirates, but something that has evolved through millions of years. Some valuable minerals and rare-earth metals essential for today’s technological development are found in great abundance on the sea floor.

For example, potato-like rocks called polymetallic nodules at the bottom of the ocean contain cobalt, nickel, copper, and manganese, all of which are used in the manufacturing of batteries, mobile phones and electric cars. Scientists have been aware of these resources since the late 19th century, but the technology didn’t allow for their commercial exploitation until recently.

While countries such as Japan, South Korea and Papua New Guinea have started extracting these raw materials from their seas, the real prize lies in international waters. No commercial activity has been conducted yet in these non-flagged seas, but the first applications for deep seabed mining in international waters could be approved as soon as 2023.

‘Deep seabed mining’ is the term used to describe the extraction and collection of minerals and metals from the seabed. Three main types of deposits are of interest. First, those polymetallic nodules, are usually found in depths between four and six kilometres and are rich in metals. Polymetallic sulphides are the second category. Formed around hydrothermal vents – openings on the seabed from which geothermally heated water discharges – at one to four kilometres, they contain copper, lead, zinc, gold, and silver. Finally, there are cobalt crusts, which, as the name suggests, are rich in cobalt but also contain vanadium, platinum, and nickel. These crusts form on sediment-free rocks around oceanic seamounts beneath 600m and up to seven kilometres deep.

The Metals Co. has collected 3,000 tonnes of polymetallic nodules from the sea bottom, shown here in the hold of the company’s Hidden Gem vessel

The Metals Company is one party interested in mining polymetallic nodules to build batteries for electric cars. It promises to, “enable the battery-powered shift to clean energy and electric vehicles with the lightest planetary touch”. But while this mission may sound noble and offer a potential solution to global warming and raising carbon levels, it’s highly debatable whether deep seabed mining indeed has such a light touch. Deep seabed mining would lead to irreparable damage to fragile deep seabed ecosystems and marine habitats, the disruption of the sea floor and marine food chains, noise pollution, and the spill of wastewater into the sea, which may result in the complete destruction of various deep-sea species. It’s easy to imagine the deep seabed floor as a desert devoid of life. However, it is a rich ecosystem inhabited by various species, many still undiscovered.

According to Kris Van Nijen, the managing director of Global Sea Mineral Resources, a company contracted by Belgium to conduct deep-sea mining, this creates a sustainability paradox as, “there is not one solution that does not impact biodiversity that helps to mitigate climate change, because, in the end, we have to do something and we have to make choices.” Reports by the World Bank and the International Energy Agency state that current global clean energy mineral needs cannot be met by recycling alone. An increase of up to 500 per cent in the global demand for some minerals, including cobalt and nickel, is expected by 2050. Tae-Yoon Kim, the International Energy Agency’s energy analyst, says that “recycling can have a major role, probably, after the 2030s”. If we want to switch to cleaner energy, such as electric and solar, and reduce our carbon emissions, we are currently dependent on mining.

It is precisely this argument that proponents of deep seabed mining emphasise. According to an article published this year in the Journal of Cleaner Production, “when comparing to land-based commodities, deep-sea sourced commodities have the potential to reduce the environmental footprint up to 38 per cent”. A study from 2020 found that “deep-sea mining can perform better than terrestrial mining, with a decrease of 70 per cent of climate change impacts to produce battery materials”. While the findings of these studies sound promising, it should be noted that both were financed by companies contracted for deep seabed mining. In addition, while carbon emissions from the deep seabed would be slow to be released into the atmosphere, the extraction process would still weaken the ocean’s capacity to absorb carbon.

Companies are already eyeing the potential riches of deep-sea mining

As the ocean is the world’s largest carbon absorber, ingesting a substantial portion of greenhouse gas emissions, this could have adverse effects sooner than expected. Since the deep seabed floor is outside any one state’s control, the governance of its resources is unusual and often controversial. The development of deep seabed mining and the protection of the deep seabed environment is in the hands of a global organisation, The International Seabed Authority, which ensures that the activities on the deep-sea floor are conducted to the benefit of humankind.

Since the resources lie outside the waters belonging to any one state, according to the United Nations Convention on Law of the Sea, which governs the deep seabed among the 167 states that are party to it, the resources are a common heritage to humankind. This means that the exploitation of those resources has to be done for the benefit of humanity as a whole, including future generations, and not only for the benefit of individual companies or countries. The International Seabed Authority is currently presented with a difficult task: by July 2023, it must develop a mining code that will regulate commercial mining or, in the absence of the code, consider applications for the licenses with whatever regulations are in place at the time. In doing so, they will need to consider the damage caused to the environment.

However, since little is known about the deep seabed, the risk of destroying marine species before even discovering them does exist, and the consequences can be far-reaching. For example, we could lose organisms that could be used for medical purposes or that are essential for the ocean’s health, which could lead to a collapse of the food chain in a region. And the regions proposed for mining are not small; each mining operation collecting polymetallic nodules would strip between 8,000 to 9,000sqkm of the seabed over the period of one license, which, it’s been proposed, would be granted for 30 years.

With the ocean already under stress from climate change, plastic pollution, and overfishing, this could lead to a catastrophic outcome. Currently, the deep seafloor is being explored, and experimental mining is being developed by several governments, state-owned companies, and corporations. It involves states in Asia-Pacific, including China, the Cook Islands, India, Kiribati, Nauru, South Korea, Japan, Singapore and Tonga.

There are concerns that the extraction process would weaken the ocean’s capacity to absorb carbon dioxide

China, as the biggest consumer and importer of minerals and metals, is one of the most influential parties in the deep seabed discussion and may be the first country in the world to start deep seabed mining. However, it is not the only country in the region with a keen interest in the industry: Singapore and Japan have high stakes too. Politically, engaging in deep seabed mining could be desirable for many countries. However, land mining is known to have negative connotations stemming from the displacement of communities, environmental degradation, poor working conditions, child labour, and even triggering armed conflicts.

Deep seabed mining does not entail such risks: it is conducted mainly by large machines operated by trained staff. However, it will affect marine wildlife hidden from the eyes of the average citizen of states involved in seabed exploitation. For exploration before and after 2023, a license is to be granted by the International Seabed Authority, and the mining company needs to be ‘sponsored’ by a state. This means that the sponsoring state will assume all responsibility and liability for the company concerning the mining activities. Since the sponsoring state would get some financial incentive, many small island states such as Nauru and Tonga have shown a willingness to sponsor mining activities. However, as any damage arising from deep seabed mining activities can have resounding environmental impacts, the liability of the sponsoring state can potentially exceed any financial benefit those small developing countries are incentivised with.

The risk undertaken by the government may, in such an instance, leave generations in financial hardship. It is important to note that deep seabed mining will not simply replace land mining. If no balancing regulations and programmes are undertaken, such mines will merely be a new front for environmental destruction. Additionally, enforcing environmental regulations protecting deep-seabed wildlife may be particularly difficult since the mining would be conducted at great depths, which are hard to access and monitor independently.

Deep-sea bed mining offers smaller nations potential riches, but not without risks to the environment

Effective oversight by the International Seabed Authority and environmental agencies may also be challenging. Given all the uncertainty about the environmental risks to the marine habitats of the deep seabed, some big companies such as BMW, Volvo, Google and Samsung – plus states including Chile, Fiji, Palau and Samoa – have joined a moratorium on deep-seabed mining until more is known about the ocean and risks deep-seabed mining entails.

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