The Environmental Protection Authority's split decision to approve seabed mining by Trans-Tasman Resources is an outrage, Te Kaahui o Rauru kaiwhakahaere Anne-Marie Broughton says.
"We will be appealing the decision. It is just plain wrong, as evidenced by two of the four commissioners dissenting against the approval."
The Waverley-based iwi has been through a wide range of emotions in the last few days, she said, from anger, sadness and frustration to steely determination to overturn the decision.
"We know we are not alone - we've received a huge number of messages from our uri (dscendants) and the wider community who feel the same way."
The decision is doubly frustrating with Government allocating funding to clean up freshwater earlier in the same week it approved work that will devastate the underwater environment, Ms Broughton said.