Dismantling Germany's Lubmin nuclear plant, piece by piece

Dismantling Germany's Lubmin nuclear plant, piece by piece
By Sebastien ASH
Lubmin, Germany (AFP) April 11, 2023

At a former nuclear power plant near Lubmin on Germany's Baltic coast, workers in the disassembly hall are chopping up a bulky grey section of a pump from inside one of the reactors.

A bandsaw slowly eats its way through the part, cutting it into smaller chunks that will fit in the decontamination units.

Those pieces will be blasted with iron sand, removing a dangerous top layer of material to be packed up and stored away from harm.

In mid-April, Germany's last three nuclear plants will go offline. But as their working life comes to an end, the painstaking task of decommissioning and dismantling the units begins.

The facility near Lubmin, built by East Germany's communist government and also known as the Greifswald nuclear power plant, was closed in 1990 with reunification.

But it will still be several decades before the work here is done.

"These nuclear power plants were built to last forever," said Hartmut Schindel from site manager EWN, so taking the plant apart has been a learning process.

"No one was responsible for the decommissioning in the 1960s" when the plant was first designed, Schindel said.

- 'Massive amount' -

In all, workers at the plant have 1.8 million tonnes of material to sort through and shift.

"It's a massive amount," said Schindel, who first joined the plant in the former East Germany in 1976 and was later responsible for the disposal of nuclear waste.

The vast majority of the volume will be released for reuse after a lengthy administrative process, but a small percentage of contaminated material must be sequestered.

Access to the disassembly area is closely controlled. Workers strip off their clothes, put on standard-issue underwear and a bright orange jumpsuit before they can enter the hall.

Exposure to radiation inside is counted by a personal meter carried in a breast pocket.

Coming out, a cubicle that speaks with a woman's voice checks for contamination, counting down from 20, asking the individual to turn around and starting the timer again before opening the exit.

Among the last items to be disposed are large components from the centre of the reactors, stored in a vast hangar on site.

Six pressure vessels and 21 steam generators lacquered in bright colours are waiting here to be chopped up.

For these, EWN is erecting a completely new disassembly hall, set to be completed in 2025.

The unit, where the most radioactive parts from the core will be sawed up under water for safety reasons, is an experimental project that could serve as a model for other decommissioning efforts, said EWN spokesman Kurt Radloff.

Meanwhile the work at the plant is set to continue into the 2060s, a good 70 years after it closed, with a total cost in the "high single-digit" billions of euros, Radloff said.

- 'More complex' -

The process of dismantling the communist nuclear plants was "more complex", not least because information was "lost" during reunification, said Christian von Hirschhausen of the think tank DIW.

But even dismantling some of the western plants could still take 30 or 40 years, von Hirschhausen said.

What is more, it was already "foreseeable" that some 23 billion euros ($25 billion) set aside for decommissioning would not be enough, he said.

"The question is then, who will pay for the additional costs?"

In all, Germany will have 29 closed reactors to decommission once the final three plants go offline.

The country's last nuclear power plants were kept running longer than planned amid fears of an energy crisis sparked by Russia's curtailing of gas exports during the Ukraine war.

But the end of nuclear is a settled debate in Germany, where atomic energy has long been a sensitive issue.

While other countries are planning new projects, the idea of a nuclear revival in Germany does not appeal to Schindel, who will retire before the works at the plant are done.

"The future does not point towards nuclear energy but other forms of energy," he said.

How to decommission a nuclear power plant
Frankfurt, Germany (AFP) April 11, 2023 - Germany's last three nuclear power plants will stop generating electricity from Saturday, but the arduous and decades-long process of decommissioning the sites is only just beginning.

Here's a look at what happens after the plants are taken offline.

- Gradual shutdown -

On the day of the shutdown, plant operators will gradually decrease electricity output.

From 10:00 pm (2000 GMT), "we will lower the facility's power output by 10 megawatts per minute," Carsten Mueller, plant manager for the Isar 2 site near Munich, told the Bild newspaper.

When the reactor's power level drops to around 30 percent, "no more electricity will be fed into the high-voltage network and the generator will be automatically disconnected from the power grid", he said.

A similar process will take place in the turbines of the Emsland plant in Germany's northwest, and at Neckarwestheim in the southwest.

The Neckarwestheim plant has already been running "at about 70 percent capacity" since mid-January, said Joerg Michels, head of the nuclear power division at energy company EnBW, which operates the site.

Bringing a nuclear plant to a halt is actually a "routine process" often used during inspections, Michels said.

"What's unusual now is that it will happen for the last time."

Once the nuclear reactor is rendered less powerful it will no longer send hot, pressurised water to the machine room, where the turbines will subsequently stop producing electricity.

Although no ceremonies are planned at Neckarwestheim to mark the occasion, management will be on-site "out of respect" for the roughly 650 remaining employees, Michels said.

- Cooling and dismantling -

Over the following days, the atomic chain reaction sustained by the nuclear fuel rods will be "completely stopped" to allow for the "cooling of the plant's nuclear cycle," Michels said.

As part of its exit from atomic energy, Germany has opted for the immediate dismantling of the plants once they have been disconnected from the grid, rather than mothballing the facilities.

At Neckarwestheim, the 193 fuel elements in the reactor's core -- which are still highly radioactive -- will be transferred to a water-filled pool in an adjacent building.

The fuel elements will remain immersed for three to five years until they are packed into special "Castor" casks for interim storage.

The dismantling of each component of the power plant will start "at the beginning of next year," once all the permits have been obtained, Michels said.

"We are well prepared," he added, given that EnBW already has four other reactors undergoing dismantling.

The dismantling of Germany's last three nuclear installations is expected to take around 15 years.

- Final resting place -

Germany plans to bury its highly radioactive waste deep in the ground.

But the decision on where exactly this last resting place should be is taking longer than planned -- with suggested locations often running into opposition from nearby residents who fear health hazards.

A choice on the final repository was initially due by 2031, with the aim of having the site be operational by 2050.

But late last year the German body in charge of nuclear waste disposal said a suitable location would likely be found only between 2046 and 2068.

Once the site has been identified, the planning, licensing and construction of the repository is expected to take around two decades.

The final repository eventually selected must be able to safely store radioactive waste for a million years.

In the meantime, the highly radioactive waste will be held in specially designed interim storage facilities.

For medium- and low-level radioactive waste, a permanent repository has already been found at the former Konrad iron ore mine near Salzgitter in central Germany. The site is set to become operational in 2027.

"More than 30,000 generations will still be affected by the consequences of nuclear power technology, which has only been used in our country for 60 years," former environment minister Barbara Hendricks said in 2017.