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Predicting the stability of open stopes is a challenging task for underground mine engineers. The introductory part of this paper presents main issues related to stability and safety of soil and rock mass in course of large earthworks and underground works. On the basis of former studies, this paper reviews the research findings on stope stability by the methods of Mathews and Potvin in the stoping design for rock salt mines operating at depths greater than 1 km under conditions of secondary stress fields, as well as the rock mass quality assessment by Barton’s method. The conservative stope design has been performed for a few scenarios of design parameters. In conclusions, it is underlined by the stability graph at the given parameters, that in the first case-study scenario, HR is 4.5 m and the Mathews–Potvin stability number is 68 m. It is concluded that the stopes will be stable and preserve their shapes. On the basis of presented case study (stope stability assessment in the test halite–polyhalite–polymineral salt deposit was carried out for a few scenarios at maximal effective stresses and under conditions of jointing), the authors provide the general provisions on salt rock mass assessment at great depths.

Using the applied theory of honeycomb structures, the authors propose and evaluate mining system alternates based on the structure of honeycombs for a rock salt deposit. The new-developed nature-like convergent geotechnology enables the loss of the useful mineral to be reduced from 40–60% to 15% at the preserved geodynamic safety of mining. The scope of the discussion embraces the variants of ore extraction from vertical stopes bottom-up using assemblies of mechanized equipment and top-down with a mechanical device reaming a pilot hole for useful mineral to be by-passed to an accumulation horizon.