Years of dismantling await Germany's nuclear exit

With the government's decision to wind down nuclear power, Germany's active plants are set to begin the laborious process of decommissioning. DW went to a decommissioned plant to see firsthand what this process entails.

Secluded in the lush woods of northern Brandenburg, directly between two of the eastern German state's most popular lakes, a cluster of odd-looking structures sits on an expanse of land spacious enough for at least a nine-hole golf course.

The site, some 90 km (55 miles) north of the capital Berlin, is home to the Rheinsberg nuclear power plant, one of the first of its kind to be built in the former East Germany - or all of Germany, for that matter - and the first to close.

Yet Rheinsberg is not all that 'closed.'

Since 1995, not a single watt of electricity has been generated by the Soviet-built pressurized water reactor that once stood here, but still the buildings that housed it - and the workers that operated it - remain.

The buildings are severely contaminated, and after 16 years the workers still face the task of dismantling them, which is an undertaking that has proved far more complicated than planners anticipated when the plant was conceived and constructed in the early 1960s.

Work in progress

Jörg Möller, project manager at Rheinsberg, took me on a tour of the premises to see  firsthand how much work has already been put into dismantling and decontaminating the site.

It took five years to remove the reactor core"We spent five years planning the removal of the reactor alone," Möller told me amid stark droning in the main hall, where the 125-ton object once stood.

"We decided to transport the reactor in whole instead of cutting it apart, which is often the practice. A massive crane was used to lift it out of its embedding 23 meters under the ground and onto a cargo train for transport. This was truly spectacular."

Several such operations at Rheinsberg, however, are still incomplete - like the removal of the vats that contained the coolant used to keep the reactor from overheating.

The enormous radioactive canisters will have to be dismantled using a diamond saw before they can be transported to an interim storage facility near Greifswald on the Baltic Sea coastline - a process Möller said would take at least another year to finish.

Contamination lingers

There are two ways to decommission a nuclear power plant "successfully." The first option is to dismantle and remove all structures from the grounds, allowing for complete redevelopment, or what is known as a "green field" in industry parlance.

A second option is to remove all contaminated elements from the existing buildings and prepare them for use in a subsequent capacity, for instance as part of a new power plant based on other forms of energy generation.

Tons of radioactive waste have been removed from the former dumpMöller said it was unlikely that Rheinsberg would be returned to a "green field," due to the illegality of demolishing the contaminated structures and the extreme operating expense of complete dismantling.

However, it is equally impractical at the moment to "clean" the buildings and prepare them for further use, as the structures themselves are contaminated with the radioactive isotope cobalt 60 - and will remain that way for some time.

As a nuclear contaminant, cobalt 60 has a relatively short half-life, just over five years.

This means that, in theory, the Rheinsberg plant would be ready for subsequent use in around three decades, when enough cobalt 60 has sufficiently transmuted itself to nonradioactive nickel-59.

Waste dump quandary

The contamination issues are not restricted to the walls of the reactor hall, however.

Just as complex, is the issue of what to do with radioactive waste, which has been particularly thorny for Rheinsberg.

Up until 1990, when East and West Germany reunited, all radioactive waste at the plant was stored 50 meters away on the plant's grounds.

After reunification, that simple solution proved unacceptable due to security concerns and federal authorities closed the dump.

Several thousand cubic meters of liquid radioactive waste have since been removed from the dump, where today hundreds of yellow drums stand neatly stacked and a mountain of sand waits to cover up what remains a painful memory for the entire Rheinsberg operation.

Rheinsberg's reactor is gone, but contamination lingers

Before that happens, however, the building at the base of the excavation that housed the repository must be dismantled and the residually radioactive concrete removed - another process which is more complicated and time-consuming than it sounds.

Each crate of concrete that is lifted from the repository must first be measured for radioactivity.

Concrete under accepted levels of radiation is pulverized and added to the mountain of sand – which has meanwhile reached a height of some 40 meters.

The contaminated crates, like the radioactive waste before it, await transportation via specialized CASTOR containers – the rail deliveries frequently blockaded by anti-nuclear campaigners - to an interim storage site near Greifswald.

'Nowhere to land'

The issue of where to store radioactive waste permanently is another obstacle confronting Germany's exodus from nuclear power.

The key to any sustainable nuclear decommissioning is the creation of a final storage site, according to Felix Mathes, research coordinator at Freiburg's institute for applied ecology (Öko Institut).

The final destination for nuclear waste remains unknown"We can compare the situation with an airplane that has taken off and after it is long in the air the controllers begins to look for places to build the runway," Matthes said at his office in Berlin. "We are flying - and flying and flying - and we still have nowhere to land."

For decades, Berlin has wanted to build a deep underground repository in the salt mines near Gorleben - a poor area in Lower Saxony near the former East German border.

However, Mathes said those plans were now "dead," because the selection to build the site in Gorleben was based more on politics than concerns of environmental protection and safety.

Pressure on the German government to plan and build a permanent waste disposal site is gaining with the decision to wind down nuclear power.

The country's interim storage sites - where Rheinsberg has sent all of its contaminated materials - will not be able to hold the waste generated by decommissioning all of the country's 17 remaining plants.

Author: Gabriel Borrud, Rheinsberg
Editor: Nathan Witkop

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