Though the Czech state is not planning to bury spent nuclear fuel for another half-century, it is already looking ahead with the creation of an underground lab at Europe’s last uranium mine to test conditions for a repository, the news website iDnes.cz reported on Wednesday.
This year, however, Rožná is expected to produce less than 100 tonnes of uranium for use by nuclear power stations in the Czech Republic and elsewhere. It is due to close within the next two years, iDnes.cz said.
But before it is flooded for good, one part of the mine – beneath the village of Bukov – will still be active for at least a decade, albeit for a different purpose.
The Radioactive Waste Repository Authority plans to use it to set up a special laboratory for tests that will help it build a final repository for spent nuclear fuel from the Temelín and Dukovany plants.
Geologist Lukáš Vondrovic from the Radioactive Waste Repository Authority told iDnes.cz that extensive research was required.
“In various stages we will make use of surface methods and drilling. However, they have their limits. To confirm our research it’s necessary to also acquire data from underground,” Mr. Vondrovic said.
A uranium mine is the ideal spot for the authority’s purposes. It is already running two similar labs but the deepest of them is 150m below ground. However, they are considered inadequate as rock behaves very differently a few hundred metres further underground.
Work on the Bukov underground research centre began three years ago and should be completed this year. It will be primarily composed of a corridor at a depth of 320 metres.
Data collected there will be extrapolated to create a long-term model. “We need to demonstrate the safety of a repository for a hundred thousand years,” Mr. Vondrovic told iDnes.cz.
The cost of construction and long-term operation of the lab has been put at CZK 1.7 billion.
Not everybody welcomes the idea. Some argue that the geological structure at Bukov only matches one of seven sites being considered for a future spent fuel repository – the nearby Kraví Hora, which is also on metamorphic rock (the other spots sit on granite).
The existence of the lab could mean that the repository is built there in the future, Martin Schenk of the group We don’t want a Kraví Hora repository.
Mr. Vondrovic insists, however, that research carried out at Bukov will also be useful at the other six potential locations. He said the lab has been created there simply as a means of making use of the existing infrastructure.