// Closure of Underground Cavities

AISKRISTALL

The sealing of pathways in salt formations with crystallizing evaporite minerals.

Based on the knowledge of construction material technology, geochemical modeling, and rheological investigations, salt mixtures have been developed that can be mixed with saline solutions or water and pumped into the cavities to be sealed. The mixtures harden due to the formation of hydrated salt minerals, such as magnesium sulfate hydrates, into homogeneous solids, thus transitioning to a mineralogically stable end state during the construction phase. A family of construction materials has been developed using indigenous materials from the salt formation, expanding the range of materials currently considered for filling voids and creating barriers in the salt dome. Furthermore, the prerequisites for conducting safety assessments and quality assurance measures during and after the completion of construction have been established, ensuring all the necessary foundations for practical use of the construction materials.