The Dangers of Deep Sea Mining

Thomas Morris

How many phones do you go through a year? Do you ever stop to think where their components come from? With land-based sources of precious metals and elements being rapidly depleted, mining industries are looking to the deep sea to satisfy the boom in fast-paced technology that we are currently facing. But at what cost?

You’re probably reading this blog article off your mobile device or laptop. This clean, ergonomic piece of technology is, essentially, a composite of dirt. This dirt is mined, processed, transported, formed and reformed into the clever little design it is now. In the last 4 years, Apple has averaged over 200 million iPhones per year… now, that’s a lot of dirt. Unfortunately, the minerals within the dirt that make up your device are finite. Once we remove and process all these essential compounds from the Earth... they’re gone. Industry is constantly looking for new sources of this stuff so they can continue making the products that we so desperately cling to. And so, with advances in technology, these industries have turned to the oceans to see what riches it provides.

Deep Sea Mining is the finding and removing of minerals from the depths of the oceans. The particular minerals that these companies are looking for include manganese nodules, cobalt crusts, polymetallic sulphides (which contain valuable metals such as silver, gold, copper, manganese, cobalt, and zinc.) and other rare earth elements. Many of these elements will be processed to be placed in the devices we all know and depend upon (phones, laptops, iPads etc). For example, the batteries that power your mobile device use manganese/lithium cobalt oxide, the electronics have traces of gold, copper, silver, tin, and lead, and the screens use an indium (rare earth metal) tin oxide to conduct the electricity that makes your phone responsive to touch. 

How many phones do you go through per year? Photo: Pixabay

How many phones do you go through per year? Photo: Pixabay

Interest in mining these compounds from the ocean depths began in the 1960’s, but only gained serious traction from mining companies from 2010 onwards. Interest remained low from the 1960’s to 2010 for 3 reasons; prices for these minerals didn’t make it commercially viable; there wasn’t any legal framework to control the mining of these compounds from the high seas; and finally, the engineering conundrum associated with mining minerals at depths of 5000 m or more from the ocean’s surface. As of 2010, the creation of new regulations for the exploration of the seafloor and the introduction of marine protection zones has stimulated interest in mining deep sea minerals, resulting in the awakening of this field. 

The environmental impacts of mining the ocean floor were recognised quite early on in it’s inception. Some of these include:

  • Widespread habitat destruction (approx. 25,000 km2) 

  • The impact of sediment-laden plumes to mid water species, and the down current effects of this sediment settling and burying bottom dwelling species.

  • Slow recovery potential of seabed ecosystems

  • Noise throughout the water column and light pollution to areas that may have never seen light before.

What makes deep sea mining difficult to digest, is the lack of opportunity for mitigating these environmental impacts. With land based mining, many mines assist with the restoration of the land once the minerals have been removed. In the ocean depths, many of the impacts are irreversible, or these environments may take a significant amount of time to recover. To complicate matters, the remoteness of many of these sites make studying the resilience of these habitats and the species that live there nearly impossible. For example, researchers don’t know the distribution or abundance of animals that live in the abyss. We have yet to explore 95% of the ocean, and 99% of the ocean floor. So deep sea meaning could result in us destroying entire species or habitats without knowing they existed in the first place. 

We have yet to explore 99% of the seafloor. Photo: Pixabay

We have yet to explore 99% of the seafloor. Photo: Pixabay

There are strategies that could be put into place to mitigate some of the impacts listed above. These include engineering equipment and systems to limit the overall impact they may have to the ocean floor, by designing systems that minimise sediment plumes, noise and light pollution, and the use of spatial management plans to set aside areas for protection and area’s for utilization. Even though there is potential to mitigate some of these effects, widespread habitat loss is inevitable.

The reality is that all mining causes negative environmental impacts. But deep sea mining’s harmful and disastrous ramifications are balanced against societies need for wealth and the production of minerals that are vital for our everyday lives… like the little device that fits so perfectly into the palm of your hand. 

Rising Tides is a series focussing on the current threats facing our ocean, how these are being tackled and what you can do to help