Nuclear waste. Two words that can create immediate fear.
But is the government’s plan to build a repository and storage facility for the country’s radioactive waste in South Australia really to be feared?
What kind of waste will it contain and how much is it?
How will the plant protect human health and the environment so far in the future that it is difficult to imagine what society will look like?
And why is it even needed, given that Australia produces relatively little waste from a single nuclear reactor that supports medical, research and industrial applications?
Tony Irwin is a lecturer in nuclear science at the Australian National University and directed the country’s only reactor in Lucas Heights, a suburb of Sydney.
He came to Australia with years of experience in the nuclear industry abroad, including commissioning and operating eight power reactors in the UK and helping Russian engineers improve their safety after the Chernobyl disaster.
He is very familiar with the waste that Australia produces and believes the proposed facility in Napandee, on the Eyre Peninsula, is a solid plan to manage it safely and responsibly.
“This is not a dump,” Assoc Professor Irwin told AAP. “It’s a technical facility. The connotation of the word dump is that you just throw it into a hole in the ground and forget about it.
“This is a pretty sophisticated piece of equipment we’re talking about.”
It is important to understand the dual roles Napandee will have, he adds.
First and foremost, it should be a repository – a final resting place – for thousands of barrels of so-called low-level waste. Typically, items such as plastic, gloves, clothing, and filters contain low levels of radioactivity.
This is material that will need to be managed for 300 years, says Irwin, after which its radioactivity will be degraded to safe levels.
Due to its relatively low radiation exposure, it can be safely disposed of in near-surface multi-barrier systems – managed and monitored systems that are slightly above or below the ground.
Napandee’s second role will be intermediate storage for intermediate level waste – the reprocessed remains of spent nuclear fuel that operated Australia’s first reactor before it was decommissioned and replaced in Lucas Heights.
Medium-level waste is much more durable and has to be stored at greater depths in order to isolate it from humans and the environment for thousands of years.
Australia has committed to developing a separate disposal facility for intermediate level waste, but the form in which this will be done is far from being known.
As an interim solution, the government intends to move intermediate level waste from Lucas Heights to South Australia.
One possible option currently is wellbore technology, which is being investigated by the CSIRO and the Australian Nuclear Science and Technology Organization (ANSTO), which operates the Lucas Heights reactor.
By and large, it would involve drilling a deep hole in a yet to be determined location and lowering it into individual canisters about 30 cm in diameter containing the medium-weight waste before sealing the hole.
Assoc Professor Irwin says it is sensible and best practice to put low-level radioactive waste, such as the one currently stored in around 100 locations across Australia, together in a purpose-built facility.
He says the vast majority of countries that produce radioactive waste already have facilities like the one proposed in Napandee, and Australia is on the eighth after an exhausting and controversial 40 year struggle to identify a location.
“It’s the safest way to go because then it’s in a technical facility with multiple barriers, passive security, and proper surveillance based on international best practices,” he says.
Nothing is uncertain about the current situation in Lucas Heights, where around 7,000 barrels with low-level waste are neatly stacked and stored in a building, says Assoc Porf Irwin.
It is also dangerous to store intermediate level waste there, he adds.
But neither of these situations is a definitive solution, and there has to be one, says Irwin.
David Osborn is general manager of safety and technical affairs for the Australian Radioactive Waste Agency, the government agency responsible for building the Napandee facility.
Detailed designs for the site are in development, but there is an artistic impression showing the structures that will house disposal vaults and a center for curious visitors.
According to Osborn, the site in South Australia only accepts waste that is suitably packaged, conditioned and meets the strict acceptance criteria.
He says low-level waste is disposed of in rows of disposal cells – reinforced concrete vaults that are built on or partially below the existing floor level, depending on the structural requirements.
Each cell will have a reinforced concrete base and sides and will have a temporary roof over it as it is gradually filled.
“As soon as each vault is filled, it is sealed with a reinforced concrete cover, the temporary roof removed and covered with a long-term technical cover from earthworks,” says Osborn.
“This cover will include carefully crafted mounds of geological material, impermeable membranes, and earth so that each vault resembles a small mound. This protects the safes and the environment. “
As soon as the plant has reached the “post-closure phase”, there will be ongoing environmental monitoring, says Mr. Osborn.
Containers with medium-level waste are temporarily stored, while a final disposal route “for a different type of plant at a different location” is being developed.
There is currently only one in Australia. It is stored in Lucas Heights and contains 20 tons of Australian nuclear waste that was sent to France for reprocessing and returned in 2015.
A second, only partially filled with two tons of waste, is due to arrive from the UK next year.
“The design of the waste interim storage facility will take into account strict permit requirements and will retain access to the waste so that it can also be taken to final disposal in the future,” says Osborn.
“As with low-level waste, all medium-level waste is conditioned accordingly and packaged according to strict waste acceptance criteria before it enters the plant.”
Hefin Griffiths is the chief nuclear officer at ANTSO and says Australia is trying to please the International Atomic Energy Agency (IAEA) – the United Nations nuclear watchdog.
“This corresponds to the requirements of the IAEA in the search for a final disposal route instead of continuous separate storage,” he says.
“And it enables the philosophy introduced by the IAEA that the generation that benefited from nuclear science and technology should be the one to actually find that solution, rather than leave it to future generations.”
He says that low-level waste is relatively easier to find a definitive path to because it only needs to be isolated for 300 years, far less than the thousands of years it takes for medium-level material.
Still, 300 years is a long time. It should be remembered that the first industrial evolution began 260 years ago, changing every aspect of human society.
Mr. Griffiths is confident that there is enough shared knowledge to ensure that Napandee can get its low level waste job done for the time required.
In addition, it gets a little “dystopian” when timeframes of thousands of years for intermediate level waste come into play.
“We don’t know what society will look like,” he says.
“You don’t want anyone to come by and accidentally dig up this material when they may not understand what the radioactive shamrock (symbol) means.
“These are considerations that are very long-term and a bit dystopian. But we have to make sure that the disposal options really have a future that we cannot predict. “
That is why the borehole idea investigated by CSIRO and ANSTO with boreholes up to two kilometers deep is attractive.
Mr Griffiths says that as a small radioactive waste producer, Australia needs its own long-lived radioactive waste solution.
He says the cost of disposing of Australia’s material would be astronomical if Australia pursued the kind of mined geological facilities used by nuclear-powered countries that have much more and more waste to deal with.
“If we replicated this model, we would have by far the most expensive disposal costs per unit because our quantities are so small,” says Griffiths.
“For us, a borehole disposal option still offers exactly the same multi-barrier approach, still relies on a geological barrier, but can be delivered much cheaper and, in my opinion, implemented a much faster.”
Australian Conservation Foundation activist Dave Sweeney acknowledges the need for a definitive solution to all of the country’s radioactive waste but has serious concerns about the current approach.
He says the federal government recently turned over tens of millions of dollars to ANSTO to expand storage facilities in Lucas Heights, and that there is no need to move waste from there anytime soon.
He is particularly opposed to what he calls the unnecessary double treatment of Australia’s worst nuclear waste.
“The plan is that sometime in the next 100 years a future federal government would relocate this material for a deep spill to another, currently undecided location via an undisclosed and unfunded process,” he says.
He points to evidence that Carl-Magnus Larsson, CEO of Australia’s Nuclear Regulatory Authority, presented to a parliamentary committee last year.
When asked why most of the Australian waste dumped in Lucas Heights couldn’t just stay there, Dr. Larsson: “There is no such thing as unlimited storage. That corresponds to the disposal. “
“Waste can be safely stored in Lucas Heights for decades, but we have to talk long-term and even beyond the existence of ANSTO and the current facilities at ANSTO.”
Mr Sweeney says that there has never been a discussion in Australia that begins with “how best to handle this material or how we can fully manage this material and what we think is the least bad”.
“We heard it could stay in Lucas Heights for decades. How about if we use one of these decades to do something we have never done before. “
Earlier this week, the traditional owners of the Napandee site filed a lawsuit in federal court in an attempt to stop the waste disposal process.
Barngarla Determination Aboriginal Corporation has accused the government of banning traditional property owners from voting in the community that ultimately backed the facility.
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