Germany’s Federal Association for Final Storage (BGE - Bundesgesellschaft für Endlagerung) has awarded a contract to dismantle the Gorleben mine and to backfill it using the salt previously removed. The tender was won by a consortium consisting of the companies Redpath Deilmann GmbH (Dortmund) and Thyssen Schachtbau GmbH Germany (Mülheim an der Ruhr). After the mining permits have been obtained, work is expected to begin in mid-2024. The backfilling work is expected to take three years.
In September 2020, the Gorleben salt dome in Lower Saxony was withdrawn from the list of potential sites for a repository for geological reasons based on an interim report by BGE. Since then, BGE and the Federal Environment Ministry (BMU) considered how to proceed and BMU decided in 2021 that the mine should be decommissioned. The salt that was dug out for the exploration will be used to backfill it. When the construction of the shafts for the exploration mine in the salt dome began in the 1980s, the salt was transported to the surface and has since been kept in the immediate vicinity. There are currently some 400,000 tonnes of rock salt that can used to fill the mine.
Consideration of the Gorleben rock salt formation as a possible radioactive waste repository site started in 1977. Following government approval for underground exploration in 1983, excavation work began in 1986 with the sinking of the first of two shafts. However, in 2000, in line with plans for the eventual phaseout of nuclear power, work at the mine was suspended until March 2010. In 2014, the federal government and the government of Lower Saxony agreed that activities would be scaled back to what was required to keep the mine open. Underground areas that were no longer needed in order to keep the mine open were decommissioned and sealed off.
The mine will be finally closed in phases. After the mine building has been filled, the two shafts will be filled under another construction contract (Phase 2) that is still to be tendered. Finally, the site (phase 3) will be restored for use.
"By signing the contract, we are taking the first big step towards closing the mine in Gorleben," said BGE Technical Managing Director Lautsch. "The striking salt heap will now gradually disappear and the exploration mine will be filled step by step."
Image: The salt heap at the Gorleben mine (courtesy of BGE)