Howie Tamati says the planned seabed mining off the coast of Patea is untested and backs appeals against the consent granted to Trans-Tasman Resources.
The Maori Party's Te Tai Hauauru candidate was in Whanganui yesterday door-knocking and doing a walk around town before spending the evening in Whangaehu.
He said seabed mining was the of the biggest issues in Te Tai Hauauru this election.
"That's something that I'm concerned about," he said.
"Not only that they've given consent in Taranaki but that there'll be applications for consent all the way up the West Coast. That's a major."