Euradwaste '08 - EU Bookshop - Europa

The science and technology group, responsible for the scientific and technical basis of the
safety case.
The performance assessment group, responsible for the development of a system concept, the
safety concept and the approach to safety assessment, as well as the carrying out of the safety
assessment and the compilation of the safety case.
The bias audit group, responsible for ensuring that the scientific basis for safety assessment is
complete, fully documented and exploited in an unbiased manner in safety assessment.
Interaction between these groups must take place, to keep work focused on project goals, to ensure
that the knowledge and expertise of available personnel are fully exploited, and to ensure that all
personnel understand and support the safety case arguments. At the same time, a degree of independence
must be maintained, to avoid unduly biasing the work of one group by the expectations of
another. The science and technology group, for example, should be aware of the possibility of new
phenomena, even though these may not fit conveniently into existing methods or models used by
the safety assessment group.
Because of the scope of FUNMIG the present paper focuses on the interactions between “Science”
(which can be taken to be a sub-group of the science and technology group) and “PA” (which is
identical to the performance assessment group).
The scientific work of FUNMIG was divided into five components: RTDCs 1 and 2 activities were
focused on conceptually well defined (RTDC 1) and conceptually less established processes (RTDC
2), not oriented towards a specific host-rock type or disposal concept. RTDCs 3 - 5 were focussed
on specific processes of relevance in clay-rich, crystalline and salt host-rock type. In the latter case
this refers to the overburden far-field beyond the salt rock formation.
The task of RTDC 6 was to accomplish the above mentioned interaction between science (RTDCs
1-5) and PA, in particular to monitor the scientific outcome of FUNMIG with respect to its use in
future safety cases and to give PA’s feed back to the researchers. “PA” was represented by the following
European Waste Management Organisations (WMOs):
ANDRA, France (clay-rich host rocks); ENRESA, Spain (clay-rich and crystalline host rocks);
GRS, Germany (salt host rock); NDA, UK (clay-rich and crystalline host rocks); NAGRA, Switzerland
(clay-rich host rocks); ONDRAF/NIRAS and SCK•CEN, Belgium (clay-rich host rocks);
POSIVA, Finland (crystalline host rocks); and SKB, Sweden (crystalline host rocks).
The corresponding disposal concepts were presented during the first Topical Session of FUNMIG
[2].
2. Methodology
2.1 Boundary conditions
In an early stage of the project, boundary conditions to the near-field were documented for various
European disposal concepts, namely for Spain, Switzerland, UK, France and Belgium as a prerequisite
to have information on what radionuclides with which fluxes and in which concentrations may
be released from the near-field of a repository into the surrounding host rock. The results reported
in [3] identified the key radionuclides leaving the near field and confirmed the validity of the usual
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