A group opposed to ironsand mining off Taranaki's coast is set to launch a wave of protests.

From tonight, Kiwis Against Seabed Mining (Kasm) president Phil McCabe will host a series of meetings along the Taranaki coastline about what the group has dubbed "the oceanic equivalent of opencast mining".

The group is rallying against Trans-Tasman Resources' (TTR) plans to mine the seabed along the west coast of the North Island.

TTR estimates at least 200 million tonnes of ore is within its licence area which stretches from the Waikato River mouth to Whanganui.

The privately owned New Zealand-based company is looking to mine five to 10 million tonnes of ore a year, which would mean about 50 to 100 million tonnes of sand would be removed.

The ore would be exported to China or Southeast Asia.

McCabe said mining the west coast seabed for the purposes of exporting raw ore "is an economic folly" that would "degrade the Tasman ecosystem" for few returns.

"Foreign shareholders will reap the profit and we will have to deal with the impacts, which would likely include erosion and less fish in the water.

"The Taranaki and Waikato west coasts live off revenue generated by both recreational and commercial fishing and surf tourism. Seabed mining directly threatens the revenue from both sources."

Kasm spokesman Tim Rainger said the meetings were designed to debunk the industry spin.

"We certainly don't believe that the proposals we are likely to see will be of any value to the community; and will cause quite significant environment damage."

Rainger said that although Kasm did not know the exact time frame, it believed "an application was imminent".

TTR environment and approvals manager Andy Somerville said it was premature to speculate on what the environmental impact would be.

"We don't know yet exactly what we will be doing," he said. "Until you know that, you don't know what the effects will be."

- © Fairfax NZ News