Hydrothermal vent mining would destroy ecosystems that cannot exist elsewhere

Seafloor massive sulfide (SMS) mining targets mineral-rich chimneys and mounds formed at hydrothermal vents, where superheated, mineral-laden water erupts from the Earth's crust. These vents support chemosynthetic ecosystems -- the only complex ecosystems on Earth that do not depend on sunlight -- harboring species like Pompeii worms, giant tube worms, and vent shrimp found nowhere else on the planet. Mining SMS deposits requires physically dismantling the chimney structures and excavating the surrounding mounds, which eliminates both the habitat and the fluid flow pathways that sustain the chemosynthetic bacteria at the base of the food web. Research shows that destruction of key vents can have knock-on effects on vent fields hundreds of kilometers away, because many vent species have limited larval dispersal ranges and depend on specific vent-to-vent connectivity for population maintenance. Once a vent structure is mined, it does not simply regrow: new vents form only where tectonic conditions create new fluid pathways, a geological process that cannot be engineered or accelerated. The Solwara 1 project in Papua New Guinea's Bismarck Sea was the first attempted SMS mining operation; it collapsed financially in 2019 (Nautilus Minerals went bankrupt), but not before causing significant seabed disturbance during equipment testing.