A pioneering seabed mining plan by a Golden Bay company "risks ruining New Zealand's sustainable fisheries and our international reputation", a fishing industry leader says.
Chatham Rock Phosphate is about to apply to the Environmental Protection Authority for a marine permit.
The listed company, headed by Onekaka couple Linda Sanders and Chris Castle, says phosphate nodules on the seabed in 400 metres of water on the Chatham Rise are worth $6 billion, and has forecast earnings of $62 million to $100m a year for 15 years.
It has teamed up with giant Dutch multinational dredging and marine services company Royal Boskalis in a plan to suck up the phosphate, unload it at South Island ports and sell it unprocessed to the fertiliser industry in New Zealand and overseas.
Chairman and corporate affairs director Ms Sanders says the company, in the process of raising more capital through a share offer, has employed a range of experts to carefully assess the environmental impact and develop a plan to minimise any effects the large-scale suction dredging will have.
But Deepwater Group chief executive George Clement has labelled it "strip mining" and says the fishing industry will fight the plan.
Greenpeace also plans to oppose it and expects other environmental groups to follow suit.
Ms Sanders and Mr Castle, her partner and the company's chief executive, have been developing the project for several years. The resource was discovered in 1952 by New Zealand scientists, and was extensively explored during the 1970s and 80s. At the time it was deemed uneconomic to exploit.
The price of phosphate has climbed steeply since then, and with Nauru's resources long gone, New Zealand's supply of a million tonnes a year is primarily imported from Morocco.
The company says Chatham Rise phosphate has the benefit of being low in cadmium and could be marketed around the world, especially to Australia and Asia-Pacific countries, reducing the transportation carbon footprint and shipping costs.
It expects a mining licence to be granted soon.
The bigger hurdle of a marine permit requires a similar process to that undertaken by New Zealand King Salmon in seeking to expand its farms in the Marlborough Sounds. There will be a 20-day period for public submissions, and a hearing before a panel, with a decision required within 140 days from when the application is lodged, and appeals only possible on points of law.
Ms Sanders told the Nelson Mail this week that the company - which has major United States venture capital shareholders and intends to list on the Canadian sharemarket - expected some opposition through submissions and the subsequent hearing.
But it had done its best to engage with all potentially affected parties, she said, including environmentalists, the seafood industry and Chatham Islands residents, and was confident it would gain its permit.
Ms Sanders said the company hoped to have a permit early next year, allowing Royal Boskalis, which has taken an 18.7 per cent shareholding, to install specially designed suction dredging equipment on the deck of a giant ship, the Black Marlin, similar in design and size to the world's biggest heavy-lift ship, the 225m Blue Marlin, which visited Port Nelson in 2008.
Production from the 820-square kilometre area is planned to begin in mid-2015, mining 1.5 million tonnes a year.
Seabed mining has never been done at this depth but Ms Sanders said Royal Boskalis had looked at the project for 18 months before deciding to invest.
"We've got nothing to suggest, based on the 2 years' work that we've done now, to indicate there are any show-stoppers. Boskalis has done a lot of testing in their labs. We feel pretty confident they know what they're doing."
Mr Clement said the proposed mining would happen in a Benthic Protection Area, where bottom trawling is prohibited.
"The proposed strip mining for phosphate puts short-term gains ahead of the ability of New Zealand's fisheries to thrive and to continue to provide sustainable economic benefits to the country."
He said the seafood industry had worked with the Government to create Benthic Protection Areas so that the seabed ecology and species such as sponges and corals could be undisturbed. Strip mining for a "low-value mineral" would have a double-whammy impact.
"Not only would the protections put in place for these sensitive marine areas be destroyed, but the underwater pollution caused by removing up to 1.2 metres of sand and mud from the seabed over 820 square kilometres has the potential to damage hoki, ling, hake and orange roughy stocks in the area.
"This is the same as removing all of the topsoil from an area the size of Tongariro National Park and to then simply dump the parts not needed back into the ocean, to be carried wherever the currents and weather conditions dictate."
Greenpeace oceans campaigner Karli Thomas said the environmental group would be opposing the permit application.
"Industrial-scale vacuuming up the seabed isn't going to happen without some pretty devastating impacts," he said.
"The idea of doing that with untested technology in areas designated for seabed protection is madness. There's no point protecting the seabed from fishing and then sucking it up and spitting it out for phosphate mining."
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