Works on the stabilisation of the Asse mine resumed
The risk of an increase in saline solution flowing into the mine is to be reduced
The so-called backfilling of roof clefts to stabilise the Asse II mine will be resumed. Since there were no salt supplies temporarily, the works had to be interrupted between 30 June and 27 July.
Backfilling of roof clefts means that remaining cavities in chambers where no nuclear waste is stored are filled with a special type of concrete. These chambers (so-called mining districts) that are not filled with nuclear waste had been backfilled with ground salt years ago. Because this salt has meanwhile slumped, cavities have formed between the roofs and the filled-in salt. Due to the backfilling of these cavities with a special type of concrete, the stabilisation of the mine will be increased and the risk of an increase in saline solution flowing into the mine will be reduced.
Currently, the roof cleft in mining district 7 on the 490-m level is being backfilled. So far, around 446 cubic metres of special concrete have been brought into this roof cleft between 17 June and 29 June 2010. Altogether, one intends to fill more than 80 roof clefts with special concrete. Four have already been backfilled, two roof clefts are currently being backfilled..