RD&D-Programme 2004 - SKB

Clab has been expanded in recent years. The second rock cavern was completed at mid-year
2004 and is scheduled to be taken into service at the end of 2004. At year-end 2003 there
were 4,069 tonnes of fuel (counted as uranium) in the facility. The total storage capacity is
8,000 tonnes of fuel: 5,000 tonnes in the original pools and 3,000 in the new ones.
1.1.3 Transportation system
In Sweden, nuclear waste shipments go by sea, since all nuclear power plants and nuclear waste
facilities are situated along the coast. The transportation system consists of the ship m/s Sigyn,
a number of transport containers/casks and vehicles for loading and unloading. The system has
been gradually built out and augmented since the start of operation in 1982. Normally Sigyn
makes between 30 and 40 trips per years between the nuclear power plants and Clab or SFR.
The ship is also chartered out for other heavy shipments.
Low-level waste does not need any radiation shielding. It can therefore be transported in
ordinary freight containers. Intermediate-level waste, on the other hand, requires radiation
shielding and is embedded in concrete at the nuclear power plants. The waste then is shipped
in transport containers with 7–20 centimetre thick walls of steel, depending on how radioactive
it is. The spent fuel is shipped in transport casks with approximately 30 centimetre thick steel
walls. These casks are also equipped with cooling fins to dissipate the decay heat.
1.2 Facilities for research, development
and demonstration
Much of the research and development for encapsulation and final disposal of spent nuclear
fuel needs to be done on a full scale and in a realistic setting. SKB has therefore built two
laboratories – the Äspö HRL (Hard Rock Laboratory) and the Canister Laboratory – to carry
out different research and development projects. The results of these projects will provide a
basis for designing the deep repository and the encapsulation plant, as well as for safety.
1.2.1 Äspö HRL
The Äspö Hard Rock Laboratory, which was built during the period 1990–1995, is situated
on Äspö north of the Oskarshamn Nuclear Power Plant. The purpose of the HRL is to enable
research, development and demonstration to be done in a realistic and undisturbed rock
environment down to repository depth. The underground laboratory consists of a tunnel from the
Simpevarp Peninsula to the southern part of the island of Äspö, where the tunnel runs in a spiral
down to a depth of 460 metres, see Figure 1-2. The total length of the tunnel is 3,600 metres. At
ground level there are office buildings, workshops, laboratories and premises for information
activities that are gradually being built out. During the summer of 2003, another branching
of the tunnel was blasted out to accommodate new experiments concerned with, among other
things, rock mechanics and grouting technology.
Activities at the Äspö HRL
The role of the Äspö HRL has changed in recent years from developing methods for rock
investigations to developing methods for construction and operation of the deep repository. The
first goal of the activities at the laboratory has thereby been achieved. The next step is to carry
out the following tasks:
• Develop and demonstrate methods for construction and operation of the deep repository.
• Test alternative technology that can improve and simplify the design of the deep repository
without compromising its high quality and safety.
RD&D-Programme 2004 21