Plans to mine rock phosphate from the Chatham Rise took another step forward with €4 million to be spent on a final detailed design of a system to extract the rock from under the sea.

New Zealand company Chatham Rock Phosphate has agreed with Boskalis to move to phase two of its services contract to design the mining system. That work should be completed by the end of June 2013.

Earlier this year International dredging giant Boskalis took a 20 per cent stake in CRP, mainly as a prepayment for services.

Boskalis is CRP's technical partner in its Chatham Rise rock phosphate project and is a global dredging and maritime services company.

In July this year, CRP entered a contract for services with Boskalis Offshore B.V..

CRP said it was expected that the new phase of the contract would involve only a modest future cash cost, if any, to CRP.

CRP and Boskalis have already done extensive work refining the extraction system for recovering and separating phosphate nodules applying adapted and proven technologies.

CRP holds a prospecting permit to develop an undersea rock phosphate resource, 400m below the sea surface on the Chatham Rise, about 450kms east of Christchurch. It would be a world first to recover phosphate from such depths.

CRP has said it aims to produce 1.5 million tonnes of phosphate fertiliser from year one.

Based in Holland, Boskalis has a fleet of more than 1100 vessels. It operates in more than 75 countries.

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