{"id":822213,"date":"2026-07-25T04:00:13","date_gmt":"2026-07-25T04:00:13","guid":{"rendered":"https:\/\/www.newsbeep.com\/au\/822213\/"},"modified":"2026-07-25T04:00:13","modified_gmt":"2026-07-25T04:00:13","slug":"a-global-threat-for-millennia-experts-warn-australias-nuclear-submarine-legacy-will-be-weapons-usable-uranium-cache-aukus","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/au\/822213\/","title":{"rendered":"A global threat for millennia: experts warn Australia\u2019s nuclear submarine legacy will be weapons-usable uranium cache | Aukus"},"content":{"rendered":"

Australia\u2019s proposed nuclear submarine fleet will leave behind tonnes of weapons-usable uranium-235: radioactive for hundreds of millions of years, and capable of being processed into scores of warheads, nuclear experts have told a public inquiry into Aukus<\/a>.<\/p>\n

And a former White House national security adviser has told the Guardian that Australia\u2019s Aukus deal \u2013 involving the transfer of highly enriched uranium to a non-nuclear weapons nation \u2013 sets a dangerous proliferation precedent that other countries such as Iran could try to exploit<\/a>, weakening global control of the spread of weapons-usable nuclear material.<\/p>\n

Associate Prof Tilman Ruff, founding chair of the Nobel prize-winning International Campaign to Abolish Nuclear Weapons, told the Aukus public inquiry that the legacy of Australia\u2019s nuclear submarine fleet \u2013 of which each vessel will have a service life of about three decades \u2013 will be hundreds of kilograms of high-level radioactive waste. Even as waste, the submarines\u2019 spent reactor fuel will be highly enriched uranium (HEU), usable to build nuclear weapons.<\/p>\n

\u201cNo nation has resolved the huge problem of how to manage this material and there\u2019s no guarantee \u2013 given the timeframes involved and the hazards of the material over geological time \u2013 that any arrangement that we come up with could reliably isolate that material for hundreds of thousands, or millions of years.<\/p>\n

\u201cThe additional complication here is that it needs a really high level of security because, in 10,000 years, somebody could still go and dig that stuff up and build nuclear weapons with it.\u201d<\/p>\n

The uranium left behind by Australia\u2019s nuclear submarines at the end of their working lives will likely still be enriched to about 80%: the same level as the atomic bomb dropped on Hiroshima.<\/p>\n

Quick GuideUnderstanding uranium enrichmentShow\"\"<\/p>\n

What is enriched uranium?<\/p>\n

The enrichment level measures the percentage of Uranium-235 \u2013 the fissile isotope used for nuclear power generation and nuclear weapons \u2013 within a quantity of uranium.\u00a0<\/p>\n

Naturally occurring uranium contains about 99.3% of the isotope Uranium-238: only about 0.7% of naturally occurring uranium is Uranium-235, the isotope needed to sustain a fission chain reaction.<\/p>\n

The process of enrichment (usually done through spinning uranium in centrifuges) removes U-238, increasing the percentage of U-235.<\/p>\n

Most civilian nuclear reactors use low enriched uranium, enriched to between 3% and 5% (ie between 3% and 5% of the total uranium is U-235). That level is sufficient to sustain a chain reaction and make electricity. Some countries – such as France and China – run their nuclear-powered submarines on low enriched uranium.<\/p>\n

Anything above 20% U-235 is considered highly enriched (and technically, sufficient to build a weapon).\u00a0<\/p>\n

The first atomic bomb – dropped on Hiroshima – contained uranium enriched to 80%. Modern nuclear weapons use more highly enriched uranium, usually about 93%.<\/p>\n

US nuclear-powered submarines run on reactors containing uranium enriched to 93.5% at the start of their working lives. At the end of those working lives – usually between two and four decades – the uranium remaining in the reactor cores is still, on average, 83%.<\/p>\n

Photograph: Mihajlo Maricic\/https:\/\/www.alamy.com<\/p>\n

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The Australian government has repeatedly said the precise amount of high-level nuclear waste that will be left behind by its submarine fleet is classified.<\/p>\n

But documents released under freedom of information laws show Australia will be responsible for each submarine\u2019s nuclear reactor compartment, \u201croughly the size of a four-wheel drive\u201d<\/a>, and spent nuclear fuel \u201croughly the size of a small hatchback\u201d<\/a>.<\/p>\n

Leading global experts on non-proliferation have now estimated each nuclear submarine decommissioned by Australia \u2013 beginning in the 2050s \u2013 will contain about 400kg of HEU, enriched to about 80%, containing about 320kg of uranium-235 (U-235).<\/p>\n

The International Atomic Energy Agency states a \u201csignificant quantity\u201d<\/a> of highly enriched uranium \u2013 enough to make a weapon \u2013 is 25kg of contained U-235.<\/p>\n

Associate Prof Tilman Ruff told the Aukus public inquiry that the legacy of Australia\u2019s nuclear submarine fleet will be hundreds of kilograms of high-level radioactive waste. Photograph: James Ross\/AAP<\/p>\n

U-235 has a half-life of 700m years: it will be a weapons proliferation risk for millennia. And the radioactive materials generated by its fission process will be toxic to humanity and the environment for millions of years.<\/p>\n

The HEU left behind by each one of Australia\u2019s three second-hand Virginia-class submarines bought from the US would be sufficient for more than a dozen weapons.<\/p>\n

Australia\u2019s domestically built Aukus-class submarines \u2013 Australia is proposing to build five \u2013 will be powered by Rolls-Royce\u2019s in-development PWR3+ reactor<\/a>. The quantity of HEU required to power that reactor is classified but they are expected to be larger than the Virginia-class reactors, Ruff said.<\/p>\n

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The Aukus agreement<\/a> mandates that Australia is responsible for the disposal and storage of all of the nuclear waste left behind by its nuclear-powered submarines in perpetuity.<\/p>\n

By the end of the century, when all eight of Australia\u2019s planned nuclear powered submarines have been retired, Australia will be responsible for the management of \u201cat least 3 tonnes\u201d of U-235 in the highly enriched uranium spent fuel waste, Ruff told the Guardian.<\/p>\n

\u201cThat\u2019s enough for 120 nuclear weapons using the International Atomic Energy Agency standard<\/a>.\u201d<\/p>\n

Australia has spent decades reducing its HEU stocks<\/a>. There is presently less than 3kg of HEU<\/a> in the entire country, held for research purposes.<\/p>\n

Ruff told the public inquiry into Aukus, established by the Australian Peace and Security Forum<\/a>, that his primary concern over Aukus was that it exacerbated regional tensions and made Australia \u201ca higher priority target, including for nuclear attack\u201d.<\/p>\n

Protesters outside Labor\u2019s national conference in Adelaide on Friday. Photograph: Mick Tsikas\/AAP<\/p>\n

Ruff cited the work of Dr Frank von Hippel<\/a>, senior research physicist and professor of public and international affairs emeritus at Princeton University, who estimated that the reactor of a Virginia-class submarine \u2013 such as those Australia is set to buy from the US \u2013 would be decommissioned at the end of its working life still containing about 400kg of HEU, enriched to about 80%.<\/p>\n

Von Hippel, who served as an assistant director for national security in the Clinton White House, told the Guardian \u201cby the IAEA\u2019s metric, 0.4 tons of 80% enriched uranium would be sufficient for 13 implosion bombs\u201d.<\/p>\n

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\u201cThat\u2019s a lot of weapons potential there. And that\u2019s just one submarine. That is going to change the situation in Australia with regard to the proliferation potential.\u201d<\/p>\n

Von Hippel said successive US administrations had spent decades bringing thousands of kilograms of HEU<\/a> on to American soil to reduce the risk of nuclear terrorism<\/a>.<\/p>\n

Since the 1990s, about 30 countries have reduced their HEU stocks down to less than 1kg. Countries such as France and China run nuclear-powered submarine fleets on low-enriched uranium, a far lower proliferation risk.<\/p>\n

\u201cThe worry is not so much Australia as the precedent,\u201d von Hippel said, citing countries such as Iran which has previously justified enriching uranium to 60%<\/a> by saying that in the future it might want to have naval reactors.<\/p>\n

\u201cMy concern is the proliferation example that the US and Australia and the UK have established by legitimising the use of weapons-grade uranium for attack submarines by non-weapons states: they have lowered the barriers to acquisition of nuclear weapons by this action.\u201d<\/p>\n

Von Hippel said Article IV D in the Aukus agreement<\/a>, mandating Australia store and manage all spent nuclear fuel and radioactive waste, defied decades of non-proliferation efforts.<\/p>\n

\u201cThe US has been insisting that spent fuel be sent back to it, because of this concern that the uranium is still weapons usable in the spent fuel. And now, in the case of Aukus, the US \u2026 is insisting that Australia keep the uranium \u2026 setting a new kind of precedent.\u201d<\/p>\n

\u2018Highest levels of nuclear stewardship\u2019<\/p>\n

A spokesperson for the Australian Submarine Agency told the Guardian the government was committed to the \u201chighest levels of nuclear stewardship\u201d, including responsibility for \u201cmanagement, storage, and disposal of spent nuclear fuel and radioactive waste generated from its conventionally-armed, nuclear-powered submarines\u201d.<\/p>\n

But Australia won\u2019t need to dispose of high-level nuclear waste until the 2050s, when the country\u2019s first nuclear-powered boats are decommissioned, the spokesperson said.<\/p>\n

The US secretary of defense, Pete Hegseth, and the Australian defence minister, Richard Marles, at the Pentagon in December last year. Photograph: Jim Watson\/AFP\/Getty Images<\/p>\n

\u201cThat means we have time to get this decision right, including through a thorough process informed by technical advice and extensive consultation.\u201d<\/p>\n

The ASA reiterated Australia would not accept intermediate or high-level radioactive waste \u2013 including spent nuclear fuel \u2013 from any country, including the UK or US.<\/p>\n

\u201cAukus is about keeping Australians safe in the most challenging strategic environment since the Second World War. It \u2026 strengthens our ability to deter coercion and contribute to regional stability.\u201d<\/p>\n

The defence department commissioned a review of potential nuclear waste sites in 2023. It has had that report for more than two years but has consistently refused<\/a> to release it.<\/p>\n

The defence minister, Richard Marles, said last month Aukus was on track, including consideration of a nuclear waste site.<\/p>\n

\u201cWe have time to work this through<\/a>, and we will work it through. And \u2026 what we have made clear is that the disposal facility will be on existing or future defence ground.\u201d<\/p>\n","protected":false},"excerpt":{"rendered":"Australia\u2019s proposed nuclear submarine fleet will leave behind tonnes of weapons-usable uranium-235: radioactive for hundreds of millions of…\n","protected":false},"author":2,"featured_media":822214,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[64,63,44],"class_list":["post-822213","post","type-post","status-publish","format-standard","has-post-thumbnail","category-australia","tag-au","tag-australia","tag-news"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/822213","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/comments?post=822213"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/posts\/822213\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media\/822214"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/media?parent=822213"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/categories?post=822213"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/au\/wp-json\/wp\/v2\/tags?post=822213"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}