Transuranics, mercury and banned fluids discovered in Swedish nuclear waste repository

Nuclear Monitor Issue: 
#764
28/06/2013
Charly Hultén − WISE Sweden
Article

The Spent Fuel Repository (SFR) at Forsmark is the only final repository for nuclear waste in operation in Sweden today. Intended to receive short-lived nuclear isotopes, SFR has long been criticised for both its location and its design. Opened in 1988, it is a child of 1950s and 1960s thinking. Only 60 metres beneath the sea on Sweden's Baltic coast, the repository was created to leak its contents into the Baltic, which Swedish nuclear regulatory authorities still regard as an "appropriate recipient".

One of the facilities that has deposited waste at SFR is a waste treatment facility at Studsvik, another coastal site. Studsvik, too, has been harshly criticised for the effluents it flushes into the sea. It is reputed to be the number one source of caesium pollution to Baltic waters. Studsvik AB has also been a concern on dry land − time and again authorities have urged the company to improve the documentation of its waste management.

In February of this year, some 7,000 metal drums of waste stored at Studsvik were examined to determine their contents. The drums in question contain waste from the early years of Sweden's nuclear industry, when the aim was to develop a nuclear deterrent. It is, in other words, waste from weapons research. They are stored on site, pending the creation of SFL − a special repository for long-lived intermediate-level waste.

There is no proper record of the contents, and the drums are not easily examined. Deep inside several consecutive drums is a concrete block, which isolates whatever needed to be put away. An examination carried out in February, which combined gamma radiation readings and X-ray inspection of the drums, turned up a number of unpleasant surprises: fluids (roughly five cubic metres distributed over some 2000 of the drums, some of which is presumed to be nitric acid), mercury (an estimated 65 kg), lead, and transuranics, including an estimated 300 g plutonium, perhaps twice that amount according to nuclear chemist Christian Ekberg from Chalmers Technical University. Fluids, no matter what kind, are banned because they convey radioactivity so efficiently.

These finds prompted suspicions about the 2,844 drums from Studsvik that, presumed to contain only short-lived isotopes, are already stored in SFR. In early May it was determined that all the Studsvik waste, including the drums in the SFR repository, will have to be X-rayed, sorted and/or treated and then repackaged. Some materials will need to be isolated in blocks of concrete. These various operations will require a new facility.

Retrieval of the waste from SFR, the new facility, and X-ray processing will each be costly. In Sweden the processing and management of nuclear waste is financed via a surcharge on electricity. There is also a specific surcharge of 0.002 euros/kWh to cover the costs of waste from Studsvik. In other words, users of electricity will be footing the bill for decades of nonchalance on the part of the nuclear industry.

Swedish Radiation Safety Authority
The discovery raises a number of issues relating to Swedish nuclear protection philosophy. Both the shallow SFR repository and the very profitable reprocessing plant at Studsvik have their basis in how the regulatory authority, the Swedish Radiation Safety Authority (SSM), goes about assessing the environmental consequences of nuclear facilities. The starting point in SSM's approach is the number of human beings that may come in harm's way as the result of the activity in question.

Sweden is a big country with a small population (roughly 9 million). Large expanses of the country are very sparsely populated. Furthermore, it is difficult to demonstrate how pollution of the Baltic Sea affects human health. Thus, SSM may be more generous in its estimation of the amount of radiation that poses a risk. A case in point: one of the most widely criticised design features of the SFR repository is that it is planned to be filled with sea water once the last drum of waste is in place. There is no doubt that the repository will leak – "from Day One" in the words of Anders Siebert at SSM at a recent hearing. Thus "dilute and disperse" – normally a fallback strategy when the first rule, "concentrate and contain", has failed – is standard practice in Sweden.

In an international context, this approach to human health consequences is also the key to the competitive advantage a company like Studsvik enjoys − it can process scrap imported from countries like Germany, where stricter regulations might render the processes more costly or rule them out entirely.

We should also bear in mind the evolution that has taken place in the field of radiation protection. Professor Jonas Anshelm of Linköping University has analysed ideas about nuclear waste in Sweden in recent decades. Ideas about what is to be considered 'waste', the amount of waste involved, and how long it needs to be isolated, Anshelm says, have changed over the years. "In the 1960s it was encased in concrete and dumped into the sea. In the 1970s, the industry's experts assured us that the waste would fit into a chamber the size of a sports hall. In the 1960s, storage for 100 years was considered sufficient, but today the consensus among experts is that it needs to remain isolated for over a hundred-thousand years," Anshelm points out. Presumptions have changed radically, and they will most surely continue to change, he concludes.

Anshelm is seconded by Sven Odéus, spokesman for Svafo AB, the company in charge of the Studsvik waste. An investigative journalist for Swedish radio asked Odéus how the debacle could arise:

"I think it was just a case of poor management. I don't think it was a deliberate act."

"You mean, they were just careless?"

"Well, I wouldn't say 'careless'. It was the thinking of the day." (Sveriges Radio, Klotet, 6 May 2013.)

The reporter notes that the most recent drums in the Studsvik collection were packed in 1997.

Questions remain: Has the predominant thinking within the industry's waste management company, SKB, evolved? And, if not, is there a will on the part of the regulator to make it evolve?

 

Power failure at Forsmark
May 30 − one of the Forsmark reactors in Sweden was taken off line for a scheduled check-up and repairs. Shortly thereafter electrical power supply to the reactor went dead, and no emergency back-up power from the mains kicked in. Fortunately, the control room staff was able to start up the diesel generators manually.

The operator assured the public that when offline, a reactor can go without cooling several days before the situation posses a threat. Still, the incident demanded an explanation, and it turns out that the emergency back-up power supply kicks in automatically only when the reactor is online. Whether the system will be automated even during offline periods has yet to be decided.

The strange thing is that the power supply systems were overseen as recently as 2006. Then, power failure deactivated several safety functions while the reactor in question was online. Several experts spoke of a "20 minutes to meltdown" incident. That may be the reason why the regulatory agency SSM has classed this recent failure as a "Class 1" incident. Permission to restart the reactor will be granted only after a thorough report from the operator. The power supply to other reactors at the station are now under review, as well.

Upsala Nya Tidning, 31 May 2013; WISE Sweden

Please note - we made an editing error in Charly's article. The Swedish 'SFR repository' is not the planned repository for spent nuclear fuel. It is, as the second line of the article makes clear, a repository planned for short-lived isotopes, in operation since 1988. Apologies to Charly for our editing error.

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