Link to the study - European Parliament - Europa

Nuclear Decommissioning: Management of Costs and Risks
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personnel recruitment shortages (in 15 to 20 years half of the workforce, in 30 to 40 years the
complete workforce is exchanged once).
This general view is detailed further in later chapters.
The following general conclusions can be drawn:
A total of 88 reactors are currently in their shutdown stage in the EU.
The size distribution, operating time of the reactors and shutdown periods in the EU are varying
widely.
France, Germany and the UK are the most affected countries in the EU facing decommissioning
projects.
Currently only roughly 10 % of the reactors in shutdown state have reached their final
decommissioning stage while the vast majority is in different stages of decommissioning. Most
of the finalized projects are located in Germany.
2.2. TECHNICAL BASIS OF DECOMMISSIONING
Decommissioning a reactor takes place under controlled technical conditions and brings the facility
into a state that does not require limitations any more (to a state 'below any regulatory concern' or by
a complete removal) is caused by the remaining radioactive content that still is left in the facility even
if the highly radioactive spent fuel has been removed. The following provides a basic understanding
of the sources and types of radioactivity that play a role in decommissioning.
2.2.1. Activation and contamination of the nuclear reactor during operation
Radioactivity is generated in a nuclear reactor by two different processes: nuclear fission and neutron
activation.
Nuclear reactors generate electricity by means of neutron-induced fission of fissile materials such as
Uranium-235 or Plutonium-239 into fission products (such as Cesium-137) and utilize the heat
generated in this process. Fission generates more neutrons than are necessary to keep the fission
process steady. So a large portion of the generated neutrons are captured in materials such as:
Control rods,
The cooling agent (such as cooling water) and neutron moderating agents (such as boric acid),
The reactor vessel steel and the reactor vessel internals (such as the outer metal part of fuel rods,
steel structural parts, measuring equipment), and into
The bio shield 2 .
2
Bio shield: a concrete structure outside the reactor vessel that captures neutrons that leave the reactor
vessel to the outside.
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