Modern Methods of Strengthening and Sealing Salt Mines

In order to ensure safe working conditions for miners underground, many works are carried out in mines to strengthen and seal mining excavations. This article presents the successfully applied technology for removing water inflow from the unique Salt Mine. Failure to take such action may ultimately lead to the flooding of the “Wieliczka” Salt Mine (KSW). On the basis of the authors’ research studies, some of the implemented works at the “Wieliczka” Salt Mine are presented, the purpose of which is to better protect the mine against the risk of flooding with water. Thanks to this, the mine can safely survive for many more years. This article presents two innovative technologies in salt mines: (1) sealing of the rock mass surrounding the Kościuszko shaft casing in the “Wieliczka” Salt Mine, where jet injection was used as the basic method of making an anti-filter screen outside the shaft casing and classic injection as a supplementary method for sealing the anthropogenic embankment; (2) reconstruction of the internal pillar of safety by implementing a patented technology called “pipeline injection” on the example of the Mina cross-section, in which a catastrophic water inflow was previously created that threatened the existence of the “Wieliczka” Salt Mine. The first method consists of making an anti-filter screen, which is located outside the shaft housing. Unfortunately, it is not possible to perform injection works from inside the shaft housing, because the Kosciuszko shaft, as a ventilation shaft, must be open constantly. To solve this problem, it is designed as the main technology known as jet grouting, which is supplemented by pressure injection at a depth of up to several meters with continuous monitoring of the condition of the casing during injection works. The second example concerns the reconstruction of the internal pillar of mine safety in the area of the northern border of the salt deposit. In this case, the catastrophic hazard is documented, as evidenced by the inflow to the Mina transverse, which is located on the fourth level of the mine. This task was successfully completed by the implementation of a patented technological solution called pipeline injection, the details of which are discussed in this article.