The $100 million New Zealand navy ship sunk in a marine reserve just south of Samoa's main island of Upolo after losing power and hitting a reef earlier this month.
Kiwi agencies, including the defence force, have been working to minimise the environmental impact, and are considering even removing the mighty wreckage from the sea floor.
Commodore Andrew Brown, the Deputy Chief of Navy, told Radio NZ there was some leakage of fuel and oil but not of the main fuel tanks - which contain around 950 tonnes of fuel.
"We dive daily, we do shore-line patrols, and we're monitoring any remnants of the fuel and what happens to that fuel as it dissipates and moves offshore," he said.
NZ PM Chris Luxon says a decision on whether to salvage the ship is up to insurers. (Ben McKay/AAP PHOTOS)
The Samoa Observer has reported that Samoan authorities believe around 200,000 litres of diesel has leaked into the ocean, and fisherman have landed polluted catches.
"Fishermen went out at sea and came with fish that was covered with oil," Tuia Paepae Letoa, a Samoan chief of the local region, said.
"It is a very serious problem for the district... not only is this hurting our livelihood, damaging the reef and coast, it is also spreading to our other reserves we depend on."
New Zealand has not confirmed those reports, with Mr Luxon saying there had been "no contaminants or fuel or diesel on beaches (and) no loss of wildlife".
Cdre Brown said around 60 NZDF personnel has been deployed to monitor the situation in tandem with Samoa.
"We're committed to working with the Samoan government and we will continue to work from on-site and from back from New Zealand in supporting the overarching operation, and the removal of Manawanui," he said.
Mr Luxon said it would be up to the navy and the insurers as to "whether it's a salvage or a wreck".
"We now need to work to plug the small venting leaks ... but the good news is that the main fuel tanks are actually intact at this point in time, which is exactly what we want to see," he said.
All 75 crew were able to make it to shore with a few injuries sustained during a frightening overnight life raft voyage.
The wreckage has caused consternation in Samoa, which is also preparing to host the biggest event in the country's history.
Samoa is hosting King Charles and delegates including many prime ministers for the Commonwealth Heads of Government Meeting (CHOGM) next week.
There have been calls from Samoa for a formal apology from New Zealand, a former administrative power of Samoa with a history of mistreatment.
Mr Luxon said in his communications, including conversations with Prime Minister Fiame Naomi Mata'afa, he had offered regret.
"I've consistently conveyed that we are sorry that such a accident happened," he said.
"What we are very focused on, as a combined Samoa-New Zealand team, is actually making sure we stay very, very focused on the task at hand."
Mr Luxon said while in Samoa for CHOGM he was likely to visit the site if it was not a burden to the recovery effort.