A mineral exploration company's bid for marine consent to extract rock phosphate from the Chatham Rise seabed has begun in Wellington.
Chatham Rock Phosphate is seeking consent from the Environmental Protection Authority to mine from an 820 square kilometre area, about 450 kilometres off the Canterbury coast.
The company wants to mine 1.5 million tonnes of phosphate a year to be used by the fertiliser industry, but commercial fishing groups are opposed to the plans.
It has already been granted a mining permit and now needs permission from the Environmental Protection Authority (EPA).
The company's lawyer James Winchester told the EPA committee its proposed dredging process was a benign form of mining and the area was not significant for fishing or spawning.
He said the greatest risk to the fishing industry and fish was from trawling rather than the mining plans.