Bezpieczeństwo Pracy i Ochrona Środowiska w Górnictwie Number 12/2023

The article presents current mining works improving the safety of the Bochnia Salt Mine. Due to centuries of rock salt mining, intensive actions are required at the mine to protect the historic workings and surface of the area. In recent years, a sealing barrier has been constructed around the 16th-century Wielki Shaft to protect the salt rock mass from the destructive influence of external water. The mine is also carrying out intensive liquidation of redundant post-mining pits, which reduces the convergence of historic chambers and pits, and limits the extent of mining damage to surface facilities. An important task of the ongoing mining work is the protection, maintenance and preservation of the pits under historic protection. All these activities, as well as periodic inspections of the pits, have a significant impact on improving the safety of work and people underground.

The article demonstrates that the Geological and Mining Law provides the scope of documentation and permits necessary to start excavating a road tunnel applying mining technology. An example of an investment along the S3 expressway was then discussed. The 2.3-kilometer-long tunnel was constructed using the so-called New Austrian Tunnel Construction Method. During mining operations, an adit dating back to the early 20th century was encountered. After it was inventoried and the contact with the tunnel was closed, the tunnel boring process was safely completed. The final casing of the tunnel, which was gradually execured there, successively reduced the section of the excavation subject to the supervision of mining authorities.

Once reclamation is complete, post-mining areas become an excellent site for the foundation of ground-based photovoltaic structures. A huge advantage of these is their level surface, the lack of shading of the modules by trees or shrubs, and the absence of infrastructure, including sewage, telecommunications, electrical or gas networks. In turn, the foundation of photovoltaic installations on the unused surface of artificial water reservoirs (floating technology) in formerly open pits, limiting the occupancy of land, increases the possibilities for their location and allows to increase the efficiency of the installation in comparison with above-ground structures, among other things, by cooling the panels through the water surface. In addition, photovoltaic installations allow mining facilities to reduce energy purchase costs by consuming the "green energy" produced on an ongoing basis. With this approach, the money invested by the company can quickly pay off.