Technology and innovation, along with the relentless search for new mineral deposits, are taking mining into unchartered waters. Quite literally, in this case, as mining companies look to begin harvesting minerals that can be found on the seafloor.

Barely five percent of the deep ocean has been explored, but it is believed that it holds vast quantities of valuable minerals, including cobalt, copper, lithium, and diamonds. The mineral deposits that have been discovered so far on the seabed are several times higher in grade than on land – copper being one example – making seabed mining a genuine prospect for the future. However, there are some serious questions that need to be asked, particularly about the potential ecological impact of this new mode of mining.

But first, who owns the minerals that are on the seabed in international waters? Obviously, ownership and mineral rights are not as straightforward as on land, where there are defined borders.

Few realise that there are more mineral resources on the seafloor than on land

To deal with this issue, the International Seabed Authority (ISA) was established in 1994 to regulate mining in international waters, which account for about two-thirds of the world’s oceans. The ISA was established in 1994, and its 167-member countries include Zambia. The ISA, which is headquartered in Kingston, Jamaica, issues mining licences to companies which are looking to explore the seabed in international waters, and to date 27 licences have been issued. China is the country to which the single most licences have been awarded, with three. Michael Lodge, the ISA’s secretary-general says. “In the seabed, resources are incredibly rich. These are virgin resources. They’re extremely high-grade. And they are super-abundant.”

But, what about the potential damage to the ocean’s ecosystem and marine life?

To be sure, mining will always have an impact on the environment, no matter where it is conducted. On land, for example, it not only leaves the proverbial hole in the ground, but also requires vegetation or settlements to be moved, considerable infrastructure to be built, and site rehabilitation on closure.

The one obvious upside to underwater mining is that there’s nobody living at the bottom of the sea, and consequently no one to be displaced or rehoused. But what about marine life in the area being mined? Will entire eco-systems be destroyed, or will damage be localised, leaving the broader ocean unscathed?

In the absence of large-scale seabed mining, these questions are impossible to answer with any certainty at this stage. However, precisely because of the uncertainty, caution is the watchword for now.

Kristina Gjerde, a senior advisor at the International Union for the Conservation of Nature (IUCN) says: “With interest in deep sea mining growing exponentially, now is the time to ensure that lasting damage to the unique ecosystems found in the ocean depths can be prevented.”

Life on the seabed can be as rich and diverse as that found in a tropical rainforest. Gjerde has concerns that the release of toxic chemicals and sediment clouds could spread through the ocean and choke sea life. As a number of areas of the seabed already identified for mining exploration have been found to be teeming with previously unknown species of marine animal mining could have a dramatic effect on these creatures, about which we know very little.

On the other side of the environmental equation, a number of minerals which are necessary for renewable energy applications on land are found in abundance on the seabed. For example, the seabed is rich in a rare mineral called tellurium, which is used in solar panels – and solar energy is a central element of the shift away from fossil fuels to renewable energy. A rich deposit of tellurium discovered some 500km off the coast of the Canary Islands is believed to make up at least one-twelfth of the globe’s total supply of the mineral.

The leader of the expedition which discovered the deposit, Dr Bram Murton of the British National Oceanography Centre, says: “If we need green energy supplies, then we need the raw materials to make the devices that produce the energy. So, yes, the raw materials have to come from somewhere. We either dig them up from the ground and make a very large hole or dig them from the seabed and make a comparatively smaller hole. It’s a dilemma for society – nothing we do comes without a cost.”

Large-scale mining of the seabed has not yet begun, but mining at sea is not a totally new phenomenon. De Beers, one of the world’s biggest diamond companies, has been mining off the coast of Namibia since the 1960s, vacuuming up diamonds found on the seafloor. Underwater gems now account for some four percent by volume of its mining output, and some 13% by value.

Nautilus, a company based in Toronto, Canada is another company which is exploring the seabed for minerals – “massive sulphide systems”, according to its website. Early reports from the company’s first exploration off the coast of Papua New Guinea indicate that the copper grade at the site is about 7%, compared to less than 1% on copper mines in North Western Province, Zambia.

“A lot of people don’t realize that there are more mineral resources on the seafloor than on land. Technology has allowed us to go there,” says Michael Johnston, Nautilus’s CEO.

In the quest to access vital industrial and other minerals that are becoming scarcer on land, mining companies have become a lot more daring and innovative. They are demonstrating in spectacular fashion that no frontier – whether out in space or deep in the oceans – is out of reach. However, mining these new frontiers will be as much about legal ownership and environmental protection, as about pure mining.

See also: Mining metals in space