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Spectre of Maralinga hangs over Aukus nuclear waste for Indigenous communities

Behind all the pomp of the Aukus submarine deal in San Diego, there was a detail that could prove a much bigger obstacle than even the massive USS Missouri moored near the three leaders. Under the agreement, Australia will be responsible for storing high-level nuclear waste from the decommissioned reactors.

And that is no easy feat. The US and UK naval reactors that will power both the Virginia class subs and the future SSN-Aukus boats are fuelled by highly enriched uranium-235.

Once removed and decommissioned, any spent fuel from naval reactors is usually reprocessed to extract usable nuclear fuel for civilian generation and the remaining radioactive waste concentrated. The Australian government has promised not to reprocess spent fuel, which means it will likely be sent offshore.

Overseas, the process typically involves extracting usable fuel such as uranium and plutonium, and then vitrification, in which radioactive waste is concentrated and melted down into a “big glass block” weighing tonnes, said Dr Patrick Burr, a senior lecturer in nuclear engineering at the University of New South Wales. “It’s actually a very small volume, but it is extremely radioactive,” he said.

After this complicated and hugely expensive process has been completed, there remains one big question – where will this waste be stored?

For answers to this question, read the full report by Sarah Collard and Donna Lu.

Related: Spectre of Maralinga hangs over Aukus nuclear waste for Indigenous communities