"KASM is appealing because the EPA made a bad decision, a decision that we believe is wrong in law as well as in principle - and we have seen an overwhelming response against it."
Forest & Bird today also announced it has lodged an appeal in the High Court.
"The EEZ Act recognises that seabed mining could have significant impacts on the marine environment, and requires protection from such impacts," the group's chief executive, Kevin Hague, said.
"We think the EPA's decision to grant consent fails to protect the environment, and doesn't meet the requirements of the EEZ Act."
The other groups to lodge appeals are Ngati Ruanui, Ngaa Rauru, Fisheries Inshore New Zealand Ltd and Greenpeace.