Deep-Sea Mining Might Happen. So What?

An Expert Opinion: Dr. Cindy Lee Van Dover

Dr. Cindy Van Dover is the director of the Duke University Marine Laboratory. She has spent the last 30 years exploring the deep sea. Her research has led her to hydrothermal vent fields thousands of meters below the ocean surface, as well as to conference tables around the world, where she is now helping to develop regulations around deep-sea mining.

Deep-sea mining is the process of extracting mineral-rich deposits from hydrothermal vents and other deep seafloor settings. The upside is more copper, manganese, and rare earth minerals to power things like wind turbines, cell phones, and computers. The downside is … unknown. Dr. Van Dover is working with an international community of governments and industry to mitigate the collateral environmental damage that will result from seafloor mining.

How do you reconcile your passion for the deep sea with your work with the mining community?
When I first started thinking about deep-sea mining in the mid-2000s, I thought I would be long retired before mining really became an issue. I also thought, “I’ve helped explore the deep sea and love it; it hurts to think we will willingly damage this extraordinary environment.” But from conversations with the Secretary General of the International Seabed Authority and with others, seabed mining of some form or other seems inevitable. If this is so, if mining does proceed, then my role as a scientist is to use my knowledge to help minimize the environmental impacts.

I think that my generation of deep-sea scientists will be judged a century from now by the quality of environmental regulations we help to put in place. How important are the right regulations? If we don’t get it right, if we degrade the seabed, we can’t fix it.

The deep sea is not on most people’s radar. Why should we care?

As we have learned the hard way more than once, the biosphere of Earth is interconnected – what happens in one place, affects what happens elsewhere. The seafloor seems so remote to us, yet so did the ozone layer. Humans have a tremendous capacity to modify the global environment, in ways we often don’t anticipate and in ways that are very detrimental to our quality of life. Can we avoid making mistakes in the deep sea? We have to try.

Is it a free-for-all on the sea floor, or is there a governing body making sure companies and countries act responsibly?
The mineral resources of the seabed in international waters are governed by a very interesting regime. The United Nations Convention on the Law of the Sea came into force in 1994 and as part of this Convention, seabed minerals in the area beyond national jurisdictions became the common heritage of mankind, with equitable access and benefit sharing for all nations. The intent is that developing countries, land-locked countries, and geographically disadvantaged countries should have access to seabed minerals, not just the developed countries.

Where are these mineral deposits located?
There are three different kinds of mineral resources of interest to the mining industry. Hydrothermal vents associated with volcanic systems on the seafloor are copper-rich and sometimes gold- and silver-rich. Fossil vent deposits of economic interest form over thousands to hundreds of thousands of years. 
Manganese nodules are a second kind of mineral resource, found lying on top of sediments of the abyssal plain, typically beneath 5,000 meters of water. These nodules take millennia -- millions of years -- to form. 
The third major mineral resource is cobalt crusts. These crusts typically are found on seamounts and are often colonized by ancient, slow-growing corals.

The sea is vast. Can you help put the size of potential mining sites in perspective?
It IS hard to comprehend dimensions as big as the deep sea. 
 A single mining event at a hydrothermal deposit might cover an area the size of a dozen or fewer football fields. For manganese nodules, the scale of a mining area is much, much greater. Exploration lease sites for manganese nodules in international waters are extensive, the size of small countries.
We don’t yet understand what the direct, indirect, or cumulative environmental impacts might be of mining in the deep sea on such a scale.

Is there a baseline for the ecosystem services provided by the deep sea?
There are very few quantitative numbers about ecosystem services in the deep sea. This is an area of research that is critical if we are to understand how deep-sea industrialization may affect ecosystem health and ecosystem services. How can we know what is at risk, if we do not have validated quantitative models of deep-sea processes?

Is it difficult to separate your passion from the science?
I have learned to do this, to recognize that there are valid perspectives of and interests in the deep sea that are different from mine as an ecologist. As a scientist, I am obliged to give as unbiased an answer as I possibly can when asked for information about deep-sea ecosystems. The questions that I am asked by those interested in mining and environmental management of mining activities are always intellectually engaging and often difficult to answer precisely.

What do you miss most about being at sea when you’re on land?
What I love is the focus that comes with being at sea with colleagues. We are together on a ship, working toward common goals, with very few distractions. I miss that focus, the time to just do science, 24/7.

What do you miss most about land when you’re at sea?
Green. There is very little green at sea, not even on the ship. Everything is blue water, blue sky, white clouds.

*This interview has been condensed and edited.