Rena disappears piece by piece

The remnants of the Rena carbo ship is seen off the Tauranga coast. Photo / Supplied

Salvors working on the remains of the MV Rena are within days of whittling away all that's visible of the wrecked cargo ship.

Since last year, US-based Resolve Salvage and Fire has removed 1006 tonnes of steel from the bow of the Rena, which has been stricken off the Tauranga coast since it struck the Astrolabe Reef in October 2011.

They need about 20 near perfect working days to complete their goal of reducing the bow 1m below the water line.

A spokesperson said the nature of the final stages involved work right on or below the surf zone, which was why conditions had to be perfect to minimise potential risk to worker safety.

When salvors weren't been able to work on the bow due to weather and swell conditions, they had been working to recover debris from the sea floor between the bow and stern sections.

So far, they had removed 620 tonnes of debris, which was largely container-based scrap metal.

The latest project in the wider salvage operation involved removal of cargo and container debris in the ship's No. 4 hold, and to locate and assess the current state of two containers of beads originally located in one of its bays.

Once these two containers had been located, they need to be assessed to determine whether the beads remain, the spokesman said.

"If they are still in there, Resolve will develop a plan to remove them."

The Rena's owners and insurers are still to confirm its plans what to do with the wreck - the bulk of it being the submerged stern section - but has flagged its preference to make the site safe and leave it.

Under this plan, the company would have to apply for a resource consent, likely leading to a protracted process that could result in an Environment Court battle.

The cost of dealing with the ship, smashed into pieces on the reef off the Tauranga coast, had now shot past $275 million and is set to become one of the most expensive maritime salvages in history.