Deep sea mining (DSM) is being promoted by some policymakers and industry players as a way to secure vital minerals for green energy and defence technologies. In line with this, the White House recently issued executive orders encouraging mining activities, including efforts to fast-track deep sea mining permits while bypassing international regulatory frameworks.
However, an examination of environmental regulations under both US and international law suggests DSM cannot currently proceed legally due to the potential ecological damage.
The practice targets polymetallic nodules (PMNs)—potato-sized mineral deposits rich in cobalt, nickel, and manganese—found in abundance in the Clarion-Clipperton Zone (CCZ), a 4-million square kilometre stretch of the Pacific Ocean. While international DSM efforts are governed by the United Nations Convention on the Law of the Sea (UNCLOS), which mandates environmental safeguards, the US—though not a signatory—has its own legal provisions governing activities within its continental shelf and involving US citizens.
The International Seabed Authority (ISA), tasked with regulating activities in areas beyond national jurisdictions under UNCLOS, has granted exploration rights but no exploitation licences yet. Its regulations require the “precautionary approach” and prohibit any mining causing “serious harm” to marine environments.
In the US, the Deep Seabed Hard Mineral Resources Act (DSHMRA) bars any deep sea mining in international waters that could reasonably be expected to harm the environment. Similarly, the Outer Continental Shelf Lands Act (OCSLA), which applies to American offshore territories, demands that mining not result in “serious harm or damage” to marine, coastal, or human environments.
Despite these standards, companies like Canada’s The Metals Company and Impossible Metals are pushing forward, encouraged by recent White House support. The Metals Company has applied to mine in the CCZ, while Impossible Metals has renewed a request to mine near American Samoa.
Environmentalists warn the ecological risks far outweigh potential benefits. The habitats around PMNs are rich in unique and little-studied marine life—many species are believed to be new to science. Disturbance from mining could wipe out species permanently, especially given that PMNs take millions of years to form. Previous testing has shown that deep sea ecosystems may not recover even decades after disturbance.
Though DSM is seen as a way to secure mineral resources, current technology and scientific understanding suggest it would cause irreversible harm, failing to meet environmental criteria under UNCLOS, DSHMRA, or OCSLA. Advocates say that until mining can be done without such damage, the practice should be paused or banned outright.
