Decommissioning of 5 PreussenElektra nuclear power plants

Characterisation of reactor vessel and biological shield of 5 nuclear power plants

28 March 2021

NRG and its German partner Höfer & Bechtel work on the decommissioning of 5 PreussenElektra nuclear power plants until 2025. We take care of characterisation of the interior of the reactor vessel and biological shield and of responsible decommissioning and documented storage.

Thanks to high-quality equipment and facilities, we take high-level radioactive samples and characterise them.

NRG and Höfer & Bechtel handle the entire process together, from characterisation to safe storage.

NRG and Höfer & Bechtel are experts in the field, with extensive knowledge of the German market.

NRG and Höfer & Bechtel

The work is being carried out by Inspection Services and Laboratory Services of NRG and Höfer & Bechtel. This partnership is characterised by:

  • Years of experience in developing remote-controlled tooling for use in the nuclear industry
  • Team of engineers used to working in nuclear installations
  • Experts in the field; the right licenses, expertise and facilities
  • Radiochemical analytical capacity
  • Able to carry out the entire process together, from cutting, sampling, transport and from characterisation to packaging. Unique in the nuclear world.

About Preussen Elektra

- Energy supplier in Germany for nearly 100 years
- Operates 7 nuclear power plants in Germany
- Mission is nuclear safety
- Successful operation and decommissioning of nuclear power plants

PreussenElektra has to decommission five nuclear power plants before 2026 and was looking for a partner to take on this project. After the successful characterisation of the Grafenrheinfeld control rods, PreussenElektra established a long-term partnership with NRG and Höfer & Bechtel to do the dismantling in a professional manner.

The challenge

NRG and Höfer & Bechtel have been assigned to characterise the interior of the reactor vessel and the biological shield for 5 nuclear power stations.

The project had a number of challenges.
- The samples to be taken are meters under water.
- The samples are highly radioactive. The sample must be large enough for proper characterisation and as small as possible for safe processing by employees.
- It is not always clear what material we are dealing with.
- Laws, regulations and insights may change during the course of the project.

Taking samples

One of the challenges was taking the samples for characterisation. The material we had to measure was highly radioactive and was several meters under water.
We had to make sure that we could perform remote sampling to minimise radiation exposure for the employees. For this purpose, NRG has developed the manipulator.

The manipulator is remotely controlled. This tool takes a small sample of the material and immediately packs the sample into the sample box in one smooth movement. A safe and efficient tool for our employees.

Over the course of the project, we have further refined this process. We want samples that are large enough for good representative characterisation, but as small as possible, in order to minimise radioactivity in the laboratory.

The manipulator can also be used for dismantling the other power stations. It is designed to suit all power plants. NRG and Höfer & Bechtel are ready for the continuation of the assignment.

All data for documentation

In order to process, transport and store radioactive material safely, the materials must be carefully analysed. The analysis results and additional documents must all meet requirements.

The documentation must clearly state the level of radioactivity of the material and which radionuclides are present in the waste.

In some cases we received a sample of which we were not certain what material we were dealing with. In such a case, we must first determine which material it is with Research & Development. We act proactively and have successfully analysed the unknown samples in this project.

After the extensive characterisation of all samples in the laboratory, all data for the documentation are known and the storage documents are in order.

The power plant can now be dismantled and the waste is ready for safe storage!

Be flexible

A challenge of long-term cooperation is that laws and regulations can change. This was also the case for the storage documentation required by the German government. During the project, more data and other data were needed to prepare the storage documents.

Therefore, we had to be flexible and take several measurements. With NRG's high-quality infrastructure and Höfer & Bechtel's good project management, we were able to deliver the correct data on time for safe decommissioning and storage.

“The collaboration with Höfer & Bechtel is going really well. We have short lines of communication and we help and support each other.” Marcel Raspe, NRG

Perfect collaboration

The cooperation of NRG and Höfer & Bechtel is a perfect combination of expertise. We were able to do the whole process from characterisation to storage. We have short lines of communication and if we have to change direction, we help and support each other.

Few parties on the market can deliver this entire process. That strengthens our collaboration and makes it unique. Together we form a one-stop shop for the nuclear world.

Results so far

Höfer & Bechtel and NRG are carrying out the assignment for PreussenElektra to their satisfaction. Some great results:

- already sampled and characterised two power stations.
- tooling has already been developed and can be used in the other decommissioning projects.
- the sampling and analysis have been optimised. The whole process is now very efficient.

A good basis for the next steps of this project.

Please contact

Do you need help with one or more steps of decommissioning? I would like to tell you more

Marieke Schopman
Cluster Manager
T. +31 (0)6 1025352
M. m.vangemert@nrg.eu