RD&D-Programme 2004 - SKB

• Processes in the evolution of the repository – those processes that affect the deep repository’s
long-term safety performance.
The spent nuclear fuel and its properties are described in the information on the fuel that exists
where it is currently being stored, i.e. in Clab. The quantities of fuel expected to be generated by
the Swedish nuclear power programme are estimated annually and published in a report /11-3/.
Site descriptions are currently being compiled within the site investigation project. It is the task
of design to adapt the facility to the information on the site that has been gathered. Design also
provides suggestions on how further site investigations should be carried out to meet the needs
of design.
The design premises that comprise interpreted site data are constantly updated. Designing
the underground part consists largely of adapting the configuration of the facility to the new
information regarding the rock, for example its mechanical, hydraulic, chemical and thermal
properties.
The facility will be designed with flexibility to allow for technical advances during the long
period of time spanned by construction, operation and sealing and so that the facility will meet
safety and capacity requirements for the activities conducted there. The facility will also be
designed with regard to technical risks and costs in the construction and operating phases.
Studies of which technical solutions are most advantageous from the viewpoints of safety,
environment, performance and costs will be conducted and the results reported.
Processes in the evolution of the repository are compiled in preparation for each safety assessment.
They include all processes that influence the long-term evolution of the repository. In
many cases, for example, the processes that influence the repository’s configuration requirements
influence design loads.
Figure 11-1 shows the links between stakeholder, system and configuration requirements and
how requirements and natural and engineered conditions that control design are related. The
figure also shows the activities by means of which the design premises are updated.
Stakeholder requirements
System requirements
Design premises
Configuration requirements
Design
Facility description
Nuclear power programme
The spent nuclear fuel
Site investigation
Site description
Safety assessment
Processes in repository evolution
Figure 11-1. Relationships between requirements, premises and features and how they influence
each other. The figure also shows the activities by means of which the design premises are
updated.
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