‘Project of the century’: Swiss seek to bury radioactive waste

Storing radioactive waste above ground is a risky business, but the Swiss think they have found the solution: burying spent nuclear fuel deep underground in clay. 

'Project of the century': Swiss seek to bury radioactive waste
A picture shows the secure entrance of the acces tunnel to the Mont-Terri Rock Laboratory. (Photo by Fabrice COFFRINI / AFP)

The Mont Terri international laboratory was built to study the effects of burying radioactive waste in clay which sits 300 metres (985 feet) below the surface near Saint-Ursanne in the northwestern Jura region. 

The underground laboratory stretches across 1.2 kilometres (0.7 miles) of tunnels. Niches along the way, each around five metres high, are filled with various storage simulations, containing small quantities of radioactive material monitored by thousands of sensors. 

More than 170 experiments have been carried out to simulate the different phases of the process — positioning the waste, sealing off the tunnels, surveillance — and to reproduce every imaginable physical and chemical effect. 

According to experts, it takes 200,000 years for the radioactivity in the most toxic waste to return to natural levels. 

Geologist Christophe Nussbaum, who heads the laboratory, said researchers wanted to determine what the possible effects could be “on storage that needs to last for nearly one million years.” 

That “is the duration that we need to ensure safe confinement,” he said, adding that so far, “the results are positive.” 

Potential sites identified

Three prospective sites in the northeast, near the German border, have been identified to receive such radioactive waste. 

Switzerland’s nuclear plant operators are expected to choose their preferred option in September. 

The Swiss government is not due to make the final decision until 2029, but that is unlikely to be the last word as the issue would probably go to a referendum under Switzerland’s famous direct democracy system. 

Despite the drawn-out process, environmental campaigners Greenpeace say Switzerland is moving too fast. 

“There are a myriad of technical questions that have not been resolved,” Florian Kasser, in charge of nuclear issues for the environmental activist group, told AFP. 

For starters, he said, it remains to be seen if the systems in place can “guarantee there will be no radioactive leakage in 100, 1,000 or 100,000 years.” 

“We are putting the cart before the horse, because with numerous questions still unresolved, we are already looking for sites” to host the storage facilities, he said. 

Kasser said Switzerland also needed to consider how it will signal where there sites are to ensure they are not forgotten, and that people many centuries from now remain aware of the dangers. 

Swiss nuclear power plants have been pumping out radioactive waste for more than half a century. 

A picture shows rock core samples in the Mont-Terri Rock Laboratory. (Photo by Fabrice COFFRINI / AFP)

Until now, it has been handled by the National Cooperative for the Disposal of Radioactive Waste, or NAGRA, founded in 1972 by the plant operators in conjunction with the state.  For now, the waste is being stored in an “intermediary depot” in Wurenlingen, some 15 kilometres from the German border. 

Horizon 2060 

Switzerland hopes to join an elite club of countries closing in on deep geological storage. 

So far, only Finland has built a site, in granite, and Sweden gave the green light in January to build its own site for burying spent nuclear fuel in granite. 

Next up is France, whose Cigeo project, led by the National Agency for Radioactive Waste Management (ANDRA), plans to store radioactive waste underground in clay. 

“We are awaiting the declaration of public utility but in the meantime we will submit a request for a construction permit,” said ANDRA spokeswoman Emilie Grandidier during a visit to Mont Terri. 

Following the 2011 nuclear accident at the Fukushima power station in Japan, Switzerland decided to phase out nuclear power gradually: its reactors can continue for as long as they remain safe. 

A projected 83,000 cubic metres of radioactive waste, including some high activity waste, will have to be buried. 

This volume corresponds to a 60-year operating life of the Beznau, Gosgen and Leibstadt nuclear power plants, and the 47 years that Muhleberg was in operation before closing in 2019. 

Filling in the underground nuclear waste tombs should begin by 2060. 

“It’s the project of the century: we have carried out the scientific research for 50 years, and we now have 50 years for the authorisation and the realisation of the project,” said Nagra spokesman Felix Glauser. 

The monitoring period will span several decades before the site is sealed some time in the 22nd century. 

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Swiss nuclear power plant forced to reduce production due to warmer waters in river Aare

The Mühleberg Nuclear Power Plant in the canton of Bern has announced it is reducing its output due to the rising temperature in the river Aare, which cools the plant's reactor.

Swiss nuclear power plant forced to reduce production due to warmer waters in river Aare
The Mühleberg Nuclear Power Plant. Photo: Fabrice Coffrini/AFP.

The plant this week announced it has reduced its energy production by more than 10 per cent because of the record temperatures in Switzerland. The hottest summer since 1864 has seen water temperatures in many water bodies rise above 23 degrees Celsius, threatening aquatic fauna, and now energy supplies.

“We have reduced the reactors' power to 89 per cent,” Tobias Habegger, a spokesman for the BKW Group, the energy company that manages the plant, told Swiss news portal 20 Minutes.

The Mühleberg Nuclear Power Plant is obliged by law to reduce production once temperatures in the Aare river exceed 20.5 degrees Celsius. This is the second reduction – already on July 5th the power plant was ordered to reduce production as a safety precaution, according to the same report. 

The nuclear power station in Mühleberg is the first to have had to curtail production because of the current heatwave. The nearby power plant in Beznau is functioning normally. That plant only has to take similar safety precautions once temperatures in the Aare river exceed 32 Celsius. 

The Mühleberg Nuclear Power Plant, which has been active since 1972, will be the first in Switzerland to be disconnected as of December 2019, according to a statement by the BKW Group. 

READ MORE: Sizzling temperatures leading to 'catastrophe' for fish in Swiss lakes and rivers 

Correction, July 31st: This article originally stated that the reactor was struggling to cool the plant and has since been amended. The article has also been updated to reflect that The Mühleberg Nuclear Power Plant only has one reactor. The reduction in production is simply in order to comply with the authority‘s requirement to protect the rivers flora and fauna and not further increase the river’s temperature.