The 0.002% figure is where the company's case gets interesting [7]. Take the annual footprint out to the full licence and the project works about 34 square kilometres of seabed [1]. For 34 square kilometres to be two thousandths of one percent of a total, that total has to be roughly 1.7 million square kilometres [2]. The percentage sounds like restraint. The denominator is what produces it.
Per unit area, the same plan reads differently. Three million tonnes of concentrate off 1.7 square kilometres is about 1.76 tonnes of saleable product lifted from every square metre dredged in a year [3], and 60 million tonnes across the licence [4]. The marine scientist Bronwen Currie's objection is at bottom an economic one: phosphate is cheap, so viability has to come from volume [13]. Nothing in the licensing arithmetic contradicts her.
The other thing the licensed area does not contain is the plume. Currie says excavation and processing put sediment into the water column with consequences for ecosystems and public health [11], and that dredging risks releasing heavy metals and toxic substances buried in the sediment into the food chain and into commercial fish stocks [12]. The environmental specialist Peter Cunningham points at rocky shoreline habitats and crayfish spawning [16], which are not 120 kilometres offshore. Currie's sharper claim is that none of the environmental impact studies so far have addressed any of these dangers [14]. That is the ground on which a challenge would be fought.
The company's own framing helps its opponents more than it looks. If no immediate or urgent commercial operations are planned [8] and the onshore consents are still outstanding [3], then each of those permits is a separate decision with a separate record, and each is a place to intervene before a dredge head touches sand.
Namibia has already run this experiment procedurally. The licence dates from 2011, work stopped in 2013 over the same fishing and ecosystem concerns now being restated [10], and the state said nothing for a decade until the certificate [9], about thirteen years in all [5]. What changed over that period was not the geology, and by Currie's account of New Zealand rejecting seabed phosphate on both environmental and financial grounds [15], not the economics either. A government signed. Ocean Conservation Namibia's word for the outcome is guinea pig, on the basis that marine phosphate mining at this scale has never been done anywhere [17]. The more durable consequence is that applicants elsewhere now have a state's countersignature to cite.
