Restoring sea floor after mining may not be possible, researchers warn

A leading deep-sea mining company in the paradisal Cook Islands is aiming to start commercial production by 2030, spurred on by Donald Trump’s recent backing for the much-maligned industry.Moana Minerals wants to mine a swathe of deep ocean in the South Pacific nation for polymetallic nodules, golf-ball sized lumps studded with metals like cobalt, nickel and manganese.Efforts to start commercial-scale production have been dogged by growing calls to ban the industry until its environmental impact is clear.