On the example of the Salt Mine "Wieliezka", where in 1992 a catastrophic water influx took place, the methods of securing the mine were presented. Hole and pipeline injection was applied along with simultaneous drainage of the rock mass. Slagalkaline binder was used as a sealing slurry. It had favourable rheological conditions enabling the slurry to penetrate the rock. Some selected recipes for original sealing slurries with flow curves and strength characteristic for the scaling stone were given. The Bingham, Ostwald de Waele and Casson models were analysed.
The Salt Mine "Wieliezka" belongs to the unique world's monuments. In 1978 UNESCO put it to the First International List of World's Natural and Cultural Heritage. This object excellently represents over a 700 year's history of salt mining in Poland. In the course of a long mining activity, the rock mass started to leak locally, which significantly deteriorated the geomechanical and sealing conditions in the mine. The mine was seriously in hazard. There are known instances of flooding of mines in a similar situation. Therefore, it is generally recommended to constantly reinforce and seal the rock mass. Apart from the main injection pipeline running from the surface to the mine in the decommissioned gallery, additional pipelines were construed, the so-called deairing-injection pipelines. Their primary task was to remove air from behind the pre-constructed injection dam. On the coming slurry, the pipelines were expected to play the injection functions. The number of the pipelines was conditioned by the length of the decommissioned part of the gallery, mainly on the state of the roof. As the workings were pretty old, in some places roof slides could be observed. Therefore, to fill the gallery tightly additional pipelines were introduced. The slurry had to be dosed very precisely to the individual pipelines. It was possible thanks to the constant phone communication between the posts on the surface and underground. Besides the pipelines were equipped with valves and manometers at the inlet of the injection pipeline on the surface and directly before the injection dam.
Due to the considerable volume of the sealing slurry to be injected in a considerably short time, a highly efficient drilling equipment producing the slurry was employed as well as a patented injection method through pipelines. With this method it was possible to distribute the scaling slurry from the surface to the distant and hardly accessible workings. To achieve this objective, the existing pipeline in the shaft Kinga has been used. At certain mine levels further parts of the pipeline were led to the decommissioned galleries. The way in which scaling slurry is injected to the filled mine's void is presented in Fig. 1.
The hole injection method was carried out from the surface and workings as a part of the reinforcement and scaling activities. Vertical holes were drilled from the surface with the objective to fill the voids in the rock mass and to produce a filtration screen.