WHAT ARE THE IMPACTS OF DEEP SEA MINING?
Deep sea mining impacts pose long-term threats to marine life, ecosystems, and coastal communities especially Pacific Peoples.
The environmental damage could be severe and irreversible, with species loss and habitat destruction lasting for generations.
More than 2 million square kilometres of the Pacific Ocean are currently under exploration licences. Despite this, no commercial deep sea mine has started operating. The scale of potential deep sea mining impacts remain uncertain—and deeply worrying.
Why Deep Sea Mining Is So Risky
Loss of Biodiversity
The deep sea is not barren—it’s full of life. Scientists have discovered unique species thriving in dark, high-pressure environments. Yet only a small portion of the seabed has been studied. Mining companies often frame it as an empty wasteland, but research shows it’s a vibrant, largely unexplored ecosystem. DSM could destroy habitats that took millions of years to form, wiping out life we’ve barely begun to understand.
Unknown Cumulative Impacts
The International Seabed Authority (ISA) has issued 31 exploration permits across the Pacific, Atlantic, and Indian Oceans. Together, they cover more than 1.3 million square kilometres. If even a fraction of this area is mined, the cumulative impacts could be vast. We don’t fully understand the risks of even one mine—let alone dozens.
Sediment Plumes and Pollution
Mining operations stir up huge clouds of sediment called plumes. These plumes can drift hundreds or even thousands of kilometres, affecting areas far from the original site. They reduce water quality, smother deep-sea organisms, and block light from reaching important layers of the ocean. Many plumes also contain heavy metals and chemicals that could enter the food chain—posing risks to marine animals and people alike.
Risks to Human Health
Contaminated plumes don’t stay deep forever. The deep sea connects with shallower waters and coral reefs that Pacific communities rely on. If toxic particles spread through ocean currents, they could affect fish stocks and increase health risks for coastal populations. These threats are still poorly understood—but they’re real.
The deep ocean is intricately connected to shallower waters and coral reefs crucial to the Pacific Islanders’ way of life.
Economic Threats to Pacific Fisheries
Fishing is vital to Pacific economies. In 2018 alone, the Pacific tuna industry was worth over USD 6 billion. Many island nations rely on fisheries for income, employment, and food security. Yet the impacts of DSM on fisheries are almost completely unstudied. Only one report has tried to assess the risk—and it lacked the data needed for reliable conclusions. Without proper research, fishing livelihoods remain dangerously exposed.
Social Conflict and Unrest
Even before any mining begins, DSM is creating division. Many Pacific Islanders are deeply opposed to it, citing the damage already done by colonial legacies in land-based mining. In some places, past mining projects have led to violent unrest. There’s little evidence that DSM will be handled any better. Monitoring operations is especially hard for Pacific Island nations, who often lack the resources to enforce regulations or hold companies accountable.
Blue Peril: Mining Polymetallic Nodules in the Pacific Ocean
In 2020, the Deep Sea Mining Campaign published Predicting the Impacts of Mining of Deep Sea Polymetallic Nodules in the Pacific Ocean, a comprehensive review of over 250 scientific papers. It highlighted major knowledge gaps and confirmed serious environmental risks.
Building on this, we worked with INTERPRT and Ozeanien-Dialog to create Blue Peril—a 16-minute visual investigation that explores what’s at stake. Using ocean current modelling by Dr. John Luick, it found that waste dumped by The Metals Company in Tonga could reach Hawaiian and Kiribati waters within just three months.