Nuclear waste management:
EU-funded Research improves technology for
disposal in deep geological formations
Brussels, 19 March 2009
New technologies have been developed for the disposal of packages containing highly active and long-lived radioactive waste produced by nuclear power plants. Thanks to the results of the European Commission sponsored research project ESDRED (Engineering Studies and Demonstrations of Repository Designs), promising solutions for the disposal of this waste underground, are now available. They can be adapted to the main geological formations found in Europe as there are clay, crystalline and salt formations. The project concluded at the beginning of this year.
In the ESDRED project thirteen European National Waste Management Agencies and R&D organisations from nine EU Member States have collaborated during five years. Around € 23 million was invested, € 7.3 million of which was provided by the European Commission 6th Euratom Framework Programme for nuclear research and training.
The technical work carried out within ESDRED focused on activities needed to construct, operate and close deep underground repositories. A variety of technical options were developed and tested by the project for the disposal of waste packages as canisters or containers. These options correspond to alternative repository concepts, including disposal in horizontal or vertical boreholes and drifts underground, of canisters either conditioned above ground with a surrounding buffer or backfilled with a buffer after emplacement in the disposal cell. From now on, European waste management agencies can benefit from a range of technological options.
ESDRED made major progress in the design, fabrication and transport of specific engineered buffers, as well as associated emplacement equipment and techniques. These buffers are used for the backfilling of the annular gap between the waste package and the wall of the disposal cavity, or plugging and sealing repositories. They are generally made from bentonite (clay)/sand mixtures or cement, depending on the concept.
The consortium also developed new equipment for the safe transport and emplacement of various radioactive waste canister/container types and weights between 2 and 45 tons in underground repositories, up to hundreds of metres below the surface.
In particular, a transport and pushing robot was successfully designed and tested for 2 ton canisters for emplacement in horizontal drifts between 40m and 100m long. This equipment is on display in the Technology Centre operated by the French National Radioactive Waste Management Agency (ANDRA) in eastern France, at Saudron near the Bure Underground Research Laboratory (URL).
Another transfer and disposal equipment was successfully designed for 5.2 ton canisters in 300m deep vertical boreholes. The device is being tested within the premises of the Kraftwerk Robert Frank plant at Landesbergen, Germany.
Further two large-scale devices were successfully developed for the safe transport and emplacement of waste canisters and containers up to 45 tons in horizontal disposal drifts. One machine, based on water cushion technology, is set up at the Äspö URL in Sweden. The second machine, based on air cushion technology, can be seen at ANDRA’s Technology Centre in Saudron.
Other research focused on the development of specific plugs and rock support made from new low pH concrete formulations. One such plug is being tested at a URL for its mechanical behaviour against the swelling pressure of a bentonite buffer.
The radioactive waste management agencies involved are ANDRA (project coordinator, France), ENRESA (Spain), NAGRA (Switzerland), NDA (United Kingdom), ONDRAF/NIRAS (Belgium), POSIVA (Finland) and SKB (Sweden). The partners from technological R&D organisations are AITEMIN and CSIC form Spain, DBE TECHNOLOGY GmbH and GRS form Germany, ESV EURIDICE EIG (Belgium) and NRG (Netherlands).
More information about the project can be found on the following links:
Florian Frank, Research DG - European Commission