Thirteen cubic metres of the waste - enough to fill one third of a shipping container - will be returned to Australia by 2015 and stored for five years at the Lucas Heights nuclear facility.

The waste, which will remain toxic for centuries, was generated in Australia through the production of nuclear medicine and during scientific research.

It was taken to France for reprocessing but will be returned under and Australian-Franco government agreement and kept in a newly built storage unit.

ACF nuclear campaigner Dave Sweeney said he'd rather have the waste at Lucas Heights than placed near outback communities.

"It puts it into an area where there's established and proven security and monitoring," Mr Sweeney said.

"And where there's the greatest number of experts in Australia."

Australian Nuclear Science and Technology Organisation (ANSTO) CEO Dr Adi Paterson said most people would be surprised how small the volume of waste was.

"The store would hold around 13.2m3 of waste from spent fuel - equal to a third of one shipping container - from the old HIFAR reactor at Lucas Heights," he said.

Dr Paterson said the waste will be moved to an as yet unbuilt National Radioactive Waste Management Facility by 2020.

The Australian newspaper reported it will be shipped from France in a custom-built 6.5-metre cask with walls more than 20cm thick.

ANSTO said it will formally apply for a licence to create the new storage building at Lucas Heights, with work already underway on its design.

Lucas Heights is located in the Sutherland Shire, about 20km southwest of Sydney's CBD.