The growing demand for green metals has put sea mining under the spotlight. However, lack of regulation could cause significant environmental damage.
Mexican authorities say they never stopped granting permits. However, there are now higher standards that companies must meet to receive them.
UN has asked Grupo México to compensate the victims and rehabilitate the environmental damage caused by the Buenavista mine spill.
The company announced it has filed an appeal for revaluation of its MIA permit, which was denied for not complying with SEMARNAT requirements.