Whenever there is a debate about nuclear power in Australia, one question regularly pops up: What do we do with the waste?
It can't just be taken to the local dump along with garbage or rubble, and it has to be handled with immense care and stored in particular ways while it remains dangerous — sometimes for decades, and in the case of high level waste up to thousands of years.
Despite nuclear power generation still being a subject of political debate rather than reality, and nuclear-propelled submarines being decades away from being tied up at local docks, many Australians don't know we are already producing, processing, and storing nuclear waste.
One of the largest repositories is Australia's Nuclear Science and Technology Organisation (ANSTO) at the Lucas Heights nuclear facility, in Sydney's south.
The ABC was invited inside.
Safety first
"Let's stay standing over here, it's getting a little hotter over there," Paula Berghofer says, pointing at some dark red steel drums nearby.
The head of waste management at Lucas Heights is reading numbers flashing up on the screen of a small white box attached to her belt.
It's a dosimeter, reporting the level of radiation around us — like a compact version of a Geiger counter, without the clicking and whirring noises synonymous with radiation monitoring seen in TV and movies.
The numbers are very low, hovering around 2 to 3 microsieverts — the unit of measurement for radiation. Ms Berghofer's wearable device would start sounding a warning alarm if it got into double digits.
"We always have safety front of mind, and what that means for us is we keep our doses as low as reasonably practicable," she says.
"We don't ever take risks where we have to put people into a situation where they might get a radiation dose, no matter how small it could be."
Ms Berghofer is also wearing a second monitor, one assigned to her personally, which she wears every day, recording long-term exposure.
The type of contaminated waste coming into the vast warehouse for assessment and processing is what's classified as "low-level".
Much of it includes items like rubber gloves, gowns, glassware, and old laboratory equipment from ANSTO's nuclear medicine facility
It's still contaminated and needs to be meticulously picked through, categorised, and stored away until it's no longer dangerous, sealed away in the steel drums lining the shelves of multiple warehouses dotted across the Lucas Heights site.
Decades of legacy
Bags and bags of contaminated material sit in bins at the edge of the warehouse we're standing in.
All the waste comes from ANSTO itself. While the organisation doesn't store waste for others, it does assist with the material they produce.
"We do offer a number of services to support other communities across Australia in terms of repackaging and characterising, so we can help them better understand their waste, and then send it back to them to manage more safely," Ms Berghofer says.
It's brought into the warehouse, and scanned with high-tech machinery before ANSTO figures out the best way to store it – and for how long.
The drums have barcodes and dates, which provide vital information about their contents and when they can be safely disposed of.
"A lot of the waste that we bring in is really very quickly able to be sent out to the normal tip, because working with nuclear medicine, which generates most of our waste, we have a lot of short-lived isotopes," Ms Berghofer says.
"That content can be stored here for sometimes up to two years.
"And then we know when we can reanalyse them to check whether they can go out through waste.
"There's a barcoding system that allows us to track through the life of that waste, where it's come from, what its radioisotope content is and when it decays."
Delicate and deliberate
A short walk from the pallets of drums, stacked from the floor to the ceiling, we come across some ANSTO staff standing outside a large metal chamber.
Slowly and precisely, they're pulling on full-body protective suits and gloves – taping the sleeves to the gloves and attaching breathing aids to their waists.
They help each other with the final step – putting on bright orange hoods and face shields, making sure they're totally sealed from potential radioactive contamination.
The chamber they walk into is also totally sealed, with thick piping wrapping around it to help with ventilation.
Through the slightly cloudy windows, we can see a large box wrapped up in thick sheeting.
It's a fume hood, from one of ANSTO's laboratories, which has come to the end of its life.
The pair wave a radiation monitor over it and slowly start cutting away the sheeting. They've got some work to do to clean the fume hood and pull it apart, so it too can end up packed away in the large red drums seemingly in every corner of this facility.
There is no rush here. It is delicate, painstaking work. But vital to deal with a nuclear legacy.
Nuclear medicine, not nuclear power at Lucas Heights
ANSTO's Lucas Heights site is home to the only nuclear reactor in the country.
It's a facility used to create radioactive isotopes for use in areas such as nuclear medicine. Think of CT scans used to get a picture of how organs and blood vessels are working.
Lucas Heights' OPAL reactor is currently undergoing maintenance.
It's not used for power generation and doesn't create waste anywhere near the level of radioactive material that would come from such a reactor.
However, that's not to say there isn't decades-old nuclear waste stored at the site.
Some drums and blocks of radioactive material, encased in concrete and steel tombs weighing many tons, have been here for decades.
Among them, are remnants of the original nuclear reactor at Lucas Heights – known as MOATA – which operated between 1961 and 1995, and was decommissioned 15 years ago.
"It will remain here, safely monitored and stored, until Australia has a disposal operation available for us to send it to," Ms Berghofer says.
That's a nod to the lengthy and somewhat torrid history associated with the debate over a national nuclear waste dump – the politics of which many prefer to avoid.
Last year, the plan for a facility at Napandee, near Kimba on South Australia's Eyre Peninsula, was torn up after a Federal Court ruling in favour of the region's traditional owners.
"It's absolutely been recognised that there are a lot of small waste holders and waste generators," Ms Berghofer says.
"It's not reasonable for them to have facilities like this or teams like the one we have at ANSTO for them to be able to safely manage their waste.
"The best approach Australia has agreed to, and also internationally, is to have consolidated waste disposal facilities, and we're very happy to be supporting that process."
Offshore processing
There's another warehouse, which looks a little different, on the Lucas Heights campus.
It's newer. It's taller. It's wrapped in extra layers of security.
When you walk inside, it's striking how empty it is. Apart from two huge cylinders, standing on their ends, at one side of the building.
"While Australia has a very important role in the nuclear space, we are comparatively small, and we certainly don't have the infrastructure or really the need or desire to install what is a very large price reprocessing facility here," Ms Berghofer says.
"So it makes sense for us to have those international agreements, so that we can send this overseas to the experts, where they can reprocess it and send us back an equivalent."
Again, these canisters are also intended for a national nuclear waste dump, once it is established.