On 25 April 2017, the operator responsibilities for the Asse II mine as well as the Konrad and Morsleben repositories were transferred to the Federal Company for Radioactive Waste Disposal (Bundesgesellschaft für Endlagerung mbH, BGE). This website of the Federal Office for Radiation Protection (BfS) will therefore no longer be updated and displays the status as on 24 April 2017. You will find current information at the BGE: www.bge.de

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What happens in Asse?

Works for safe decommissioning

Backfilling of roof clefts

The cavities in the former mining chambers of the southern flank were already filled with loose rock salt material earlier on. Meanwhile this stowing material has set, so that new cavities have formed at the roofs of the chambers. These so-called roof clefts are now gradually filled with Sorel concrete. This is to reduce the deformation rate of the mine openings. The objective is to reduce the risk of an enhanced inflow of water.

In December 2009, one started filling the roof clefts of mining chamber 6 on the 532-m level. Prior to this, the accompanying drift situated above the mining chamber on the 511-m level had been widened in order to place a mobile building material facility. The salt material processed above ground (rock salt and the binder magnesium oxide) is mixed with the mixing liquid (magnesium chloride solution) in the building material facility and pumped into the mining chambers via pipelines.

Altogether, one intends to fill the roof clefts of about 90 mining chambers with Sorel concrete. This is a very laborious process, as numerous preliminary and accompanying works need to be carried out, such as the sealing of accesses to chambers, boreholes for backfilling purposes and control drillings. The salt for the Sorel concrete comes from the Grasleben salt mine near Helmstedt. The salt and other building materials, such as magnesium oxide, are delivered by rail and road.

State of 2017.02.27

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