RD&D-Programme 2004 - SKB

SKB is responsible for management and disposal of the radioactive waste that arises from
decommissioning (the non-radioactive waste is taken care of by the power companies). For this,
the transportation system needs to be modified and final repositories built. The short-lived decommissioning
waste is planned to be disposed of in an extension of SFR. The waste that has been
close to the reactor core is highly neutron-irradiated and is regarded as long-lived. This waste is
first placed in interim storage before it is finally disposed of in a repository similar to SFR but at
greater depth. This repository can be built adjacent to either SFR or the deep repository for spent
fuel. A third alternative is to build the final repository for long-lived waste at a separate site.
Conclusions in RD&D 2001 and its review
No review of RD&D 2001 indicates that any authority has any objections to SKB’s method
descriptions regarding decommissioning. On the contrary, they point out that the work is
being done in an ambitious manner. Like SKB, the authorities conclude that decommissioning
technology exists today that can be adapted to Swedish conditions.
Newfound knowledge since RD&D 2001
Experience from development of decommissioning methods is received continuously from the international
groups in which SKB and the power companies are participating. Technology development
in Sweden for rebuilds and modifications in the NPPs is also a source of experience for planning of
decommissioning of the NPPs. Newfound knowledge since RD&D 2001 is summarized in /24-2/.
24.3 Waste from decommissioning
The greatest quantity of waste obtained during decommissioning of a nuclear power plant consists
of conventional building material that is not radioactive.
Of the radioactive material, a large portion is very low-level. Following decontamination and/or
melting, quite a bit will be able to be reused. How much depends partly on how reliable the available
measurement methods are and partly on what rules for free release are applied. Today there
are no general rules for free release of material from decommissioning; instead, the regulatory
authorities decide this from case to case, since no major decommissioning projects have been
started yet. For small quantities, there are rules for removal from the NPPs.
The waste that is not released for unrestricted use will be disposed of in special repositories. The
short-lived decommissioning waste is planned to be disposed of in an extension of SFR. This extension
must be built so that the first phase is finished when dismantling of the NPPs begins. A final
repository for the short-lived waste will not be needed until 2020 at the earliest, see Figure 25-1.
Long-lived waste from decommissioning consists primarily of the reactor internals, which were
exposed to considerable neutron irradiation during operation. They comprise a small volume
(when packaged, less than 1,000 m 3 for an NPP), but need to be managed separately. They are
highly radioactive and therefore require extra shielding, and they contain large quantities of
long-lived radionuclides, which means that they should be disposed of at greater depth than the
short-lived waste. SKB plans to keep this waste in interim storage until most of the NPPs have
been decommissioned. The waste will then be emplaced in a special repository, which is planned
to be built e.g. at SFR but at greater depth. The long-lived waste from research etc that is
packaged and kept in interim storage at Studsvik will also be disposed of here.
Conclusions in RD&D 2001 and its review
SKI considers it reasonable to demand that all types of decommissioning waste must be able
to be managed from 2015. According to SKI, there is a risk that the long-lived waste will be a
bottleneck if planning and design of an interim storage facility is not started soon. According to
SSI, development of a system for interim storage of the long-lived waste from decommissioning,
as an alternative to Clab, should be given priority.
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