Fresh oil spills from Rena

It is currently impossible to know how many containers were lost overboard on Wednesday night. Photo / Graeme Brown

An oil spill response team will spend the weekend looking for signs of oil that leaked from the wrecked container ship Rena after Wednesday's storm.

Maritime New Zealand (MNZ) National On Scene Commander Rob Service said it was "impossible" to calculate exactly how much oil leaked from the wreck on Wednesday, but says it was a small amount.

He said while some of the oil appeared to reach the shoreline, it is unlikely to have had a significant impact.

A shoreline clean-up assessment technique (SCAT) team surveyed the beach from Mount Maunganui to Omanu yesterday.

They removed the larger deposits of oil, and MNZ says it is likely the smaller deposits will break down naturally in the tidal movement. SCAT teams are also heading to Maketu and Little Waihi today to see whether any oil has reached the shoreline there.

The amount of oil now remaining on the wreck is thought to be in the tens of tonnes, located in pockets throughout the ship. Salvors will strip remaining oil from the wreck when they can access the pockets, which they cannot do at the moment because of a 2-3m swell around the Astrolabe Reef.

A team of salvors are on board the ship today to examine the damage, but MNZ says the assessments will take some time, and initial examinations have shown there has been no further significant change to the wreck since Wednesday.

Since running aground on Astrolabe Reef off Tauranga in October last year, the stricken ship has spilled hundreds of tonnes of oil and shed hundreds of its containers. It is currently impossible to know how many containers were lost overboard on Wednesday night, as the swell is stopping salvors from accessing the ship's holds.

Since Wednesday a recovery team has found one container at sea, and recovered a large amount of debris that came from the wreck.

The recovery team will focus on clearing up remaining debris at the northern end of Motiti Island today, and a survey of beaches between Mount Maunganui and the Kaituna Cut is due to be carried out.

Weather conditions around the Rena are expected to ease today and remain calm over the weekend.

Since the ship's grounding, 649 containers have been recovered.