Euradwaste '08 - EU Bookshop - Europa

New Transport and Emplacement Technologies
for Vitrified Waste and Spent Fuel Canisters
Wilhelm Bollingerfehr 1 , Wolfgang Filbert 1 , Jobst Wehrmann 1 , Jean-Michel Bosgiraud 2
Summary
1 DBE TECHNOLOGY GmbH, Germany
2 ANDRA, France
In the context of the Integrated Project “ESDRED” - Engineering Studies and Demonstration
of Repository Designs [1] - funded by the European Commission, transport and emplacement
technologies for radioactive waste packages were subject of industrial demonstration tests.
Two national programmes - the German reference concept, which comprises the emplacement
of spent fuel elements in self shielding casks in horizontal drifts and the emplacement of vitrified
waste in deep vertical boreholes in a repository in salt rock, and the French concept,
which considers the emplacement of vitrified waste into horizontal cells in a repository in
clay (Argillites), were considered. In order to align the emplacement technologies for all categories
of heat-generating waste, the emplacement of spent fuel elements in deep vertical
boreholes was investigated as an alternative to the reference concept. For this alternative concept
and for the French concept, suitable transport and handling equipment was developed,
manufactured and will be tested under repository-relevant conditions on an industrial scale.
This paper briefly describes both disposal concepts, presents the transport and emplacement
systems developed for the waste packages of both emplacement concepts, and illustrates the
set-up of the demonstration test facilities. First results of the demonstration programme are
presented as well.
1. German reference concept for the disposal of heat-generating waste
In Germany, rock salt was selected in the early 1960s as the preferred host rock for a repository for
heat-generating waste because of its unique geohydrologic, thermal, and geomechanical properties
as self-healing impermeable rock. A large number of salt domes with huge dimensions, many of
them principally suitable to host a repository, exist in Northern Germany. In 1977, at the end of a
time-consuming selection process, the salt dome in Gorleben was selected for further exploration
regarding its suitability to host a repository for HLW. The corresponding reference concept for the
disposal of heat-generating radioactive waste (Fig. 1) anticipates the emplacement of canisters containing
vitrified waste in deep vertical boreholes, whereas spent fuel is to be disposed of in selfshielding
POLLUX ® casks in horizontal drifts inside a salt mine [2]. The POLLUX ® casks, carbon
steel casks weighing 65 tons each, are laid down on the floor of a horizontal drift at a depth of
840 m. The spaces between the casks and the drift walls are back-filled with crushed salt. In the
vertical disposal concept, which allows a temperature of max. 200 °C at the contact surfaces between
waste canisters and host rock, unshielded canisters with vitrified high-level radioactive waste
(HLW) are emplaced in boreholes with a depth of up to 300 and a diameter of 60 cm. In order to
facilitate the fast encapsulation of the waste by the host rock (rock salt), the boreholes are not lined.
Obtaining a license to construct a repository in Germany requires previous demonstration to the
competent authority that the level of protection (dose or risk) can be met with a high level of confi-
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