Neither the Australian Nuclear Science and Technology Organisation (ANSTO) or NSW Police would confirm it, but the vessel is expected to dock in Port Kembla on Saturday, followed by a night-time police operation through Wollongong to Lucas Heights where the intermediate-level waste will be stored.

ACF nuclear campaigner Dave Sweeney said the shipment must be allowed to pass without being disrupted.

Read more: Nuclear subs will be ready for jellyfish threat, says Defence

"This waste should come into Port Kembla and be securely transferred by skilled maritime workers and appropriate industry experts," he said.

"It should then go - without incident - to ANSTO. It should remain at Lucas Heights with the rest of ANSTO's intermediate level waste as ANSTO is best placed to manage this waste."

ANSTO said the waste is contained in a canister so secure that a person standing next to it would receive no radiation.

Mr Sweeney said the nuclear waste storage site planned for Kimba in South Australia later this decade was contested and was another "interim" option.

"This is serious waste that needs to be isolated for up to 10,000 years," he said.

"It requires active management and effective regulatory control.

"The vast majority of Australia's ILW is made and stored at ANSTO. This makes sense as ANSTO has expertise, high security, a permanent on site presence and is home to Australia's best radiation monitoring and response capacity.

"And ANSTO has storage capacity. Right now, following a $60 million dollar federal budget allocation last year, a new extended interim storage facility is being constructed at Lucas Heights."

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