ABSTRACT
During an ongoing project which succeeds previous investigations of the excavation damaged zone (EDZ) performed in the Stassfurt halite of the Asse salt mine, the EDZ evolution, especially after cutting off the contour zone, is investigated. Three test locations have been prepared in the floor of an almost 20 year old gallery on the 800-m level of the Asse mine: (1) the drift floor as existing, (2) the new drift floor shortly after removing of a layer of about 1 m thickness of the floor with a continuous miner, (3) the new drift floor 2 years after cutting off the 1-m layer. Subject of investigation are the diffusive and advective gas transport and the advective brine transport very close to the opening. Spreading of the brine is tracked by geoelectric monitoring in order to gain information about permeability anisotropy. Results obtained up to now show that EDZ cut-off is a useful method to improve sealing effectiveness when constructing technical barriers.
