Maritime New Zealand says divers are on stand-by to survey the mostly submerged stern section of the stricken Rena.
The container ship has been grounded on Astrolabe Reef, off Tauranga, since 5 October last year.
It finally broke in two after severe weather at the weekend and on Tuesday about three-quarters of the 150-metre stern slipped below water but has not moved any further on Wednesday.[image:4317:full]
Maritime New Zealand salvage unit manager Dave Billington said divers will get a chance to assess the stability of the wreck once the weather settles.
Swells of up to three metres around the Rena on Wednesday afternoon meant it was too dangerous to dive on it. Conditions are expected to ease over the next few days.
The wreck's salvors said the operation is now much more difficult as they look to recover containers and the broken vessel once it sinks to the ocean floor.
Matthew Watson, a spokesperson for salvage company Svitzer, said they have a hard task ahead, but are committed to seeing the job through.
The bow section is more vulnerable since the ship broke up, as it is fully exposed to the seas and will break up in time, so the priority is to get containers off that part of the boat as quickly as possible.
Environmental clean-up company Braemar Howells said very little container debris came ashore overnight on Tuesday.
Six containers were removed from Waihi Beach on Wednesday, with another 10 between Bowentown and just north of Waihi Beach yet to be taken away. Maritime New Zealand said 11 containers would be removed from Matakana Island as soon as possible.
Small amount of oil leaked
Maritime New Zealand said booms have been placed at Maketu and Little Waihi Beach on Wednesday in anticipation of any fresh oil washing ashore.
The authority said 12 patches of black oil can be seen in the water and current modelling showed they could wash ashore at Little Waihi and Pukehina beaches, south of Maketu, by Thursday evening.
Environment Minister Nick Smith said on Wednesday the amount of oil being released is quite small. "We're talking a quantity of probably less than 10 tonnes, as compared with the 300 tonnes that was released in October."
Six penguins with oil on them have been taken to the wildlife recovery centre and are expected to be successfully treated.
Port of Tauranga is continuing to operate but approaching and departing vessels are being advised to steer a strict path to avoid debris.
Port authorities said debris, including floating containers, are moving in a south-easterly direction away from Astrolabe Reef.