ABSTRACT
The Asse II mine is an over 100 years old salt mine in a steep inclining structure of a salt ridge in which radioactive waste was embedded from 1967 to 1978. Due to instability in a long-term sense, fracturing in the pillars and overhand stopes took place and a brine inflow has been observed since 1988. Considering the Atomic Energy Act (Lex Asse) the mine shall be closed after complete retrieval of all radioactive waste. IfG Leipzig is charged by the BGE, which is the operator of the mine, to give geomechanical expertise. This is mainly done by means of geomechanical modelling. In this article, a three-dimensional model using FLAC3D is presented that focuses on global and local assessment. Selected calculation results on stress development in the mining system and on barrier integrity are given confirming the feasibility of one particular retrieval method at the complicated geomechanical conditions.
