RD&D-Programme 2004 - SKB

KBS-3H
Basic Design Detailed engineering Demonstration Evaluation
2003 2004 2005 2006 2007 2008
Tests
Test drilling
Handling technology
Technology development
Deposition equipment, handling, design – buffer
Demonstration
Test drilling
Programme work
Tests of deposition equipment
Sealing of deposition holes
Evaluation
Reporting
Safety assesment
Studies of key issues Process report Safety report (Posiva)
Decision
Full-scale trials of function
Background
material for
decisions
Preparations
Installation and operation
Supplementary studies
Milestones
RD&D 2004 RD&D 2007
2003 2004 2005 2006 2007 2008
Figure 5. Plan for development of KBS-3H.
At the time of the permit application for the deep repository (2008 according to the timetable),
an extensive body of data will presumably be available on KBS-3H with regard to technical
feasibility, environmental aspects, costs, etc. This means it will be possible to evaluate relatively
thoroughly the potential advantages from an environmental and cost point of view. However,
it is not likely that KBS-3H will by that time have reached the developmental maturity that is
required for a decision to make this variant the reference design. The judgement SKB makes
today is that such a decision should be seen as being more long-term. This would entail that
SKB would, in conjunction with the application (which is thus based on vertical deposition),
describe the development status of KBS-3H, as well as the possibilities and consequences of
switching to this deposition method at a later phase.
In order to justify a switch to KBS-3H at a later phase, the method must be shown to be
equivalent to the reference design in terms of long-term safety, and to offer clear advantages
from other viewpoints as well. If the development work leads to this conclusion, the procedure
should be that SKB files a facility modification application, which is then examined by the
regulatory authority (SKI).
An important question is how much flexibility in the design of the deep repository remains
in various phases, in relation to what is reasonable to achieve when it comes to background
material on KBS-3H. SKB’s assessment is that a switch to horizontal deposition is possible
even in a phase when construction of the deep repository has begun, since the choice of
deposition alternative is of little consequence for those parts that are built early on, i.e. surface
facilities, descents and underground central area. This provides a time perspective which, based
on present-day knowledge, is reasonable in order to drive the development of KBS-3H so far
that a comprehensive evaluation stands on a stable foundation.
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