Rarotonga's former harbour master says a Taiwanese fishing vessel that's sunk in northern Cook Islands waters poses no significant environmental risk.
The Vanuatu-registered Yuh Pao 2 was carrying 30-thousand litres of diesel fuel when it sank almost three weeks ago after a fire broke out in the engine room.
Don Silk says the vessel is five kilometres below the surface and at that depth there's so little oxygen the fuel tanks will take thousands of years to rust.
"When you consider the Titanic which was found to have very little rust when it was discovered after 90-odd years at a similar depth."
Don Silk says even if fuel did leak, it would evaporate more quickly than heavy fuel oil.
The Ministry of Transport is to conduct an investigation into the Yuh Pao 2's sinking within the next fortnight.