## 1 Introduction  
The reclamation of post-mining areas, a mandatory responsibility of mining operators, requires the development of suitable strategies for reusing both open-pit and underground excavations. For open-pit mines, reclamation is often focused on creating water reservoirs for recreational purposes. However, in the case of hard rock quarries, where steep and high rock slopes predominate, reclamation pathways must be adapted to the site's specific characteristics. Accordingly, reclamation in such settings often emphasises natural landscape restoration, landscape-recreational functions, and educational and geotouristic opportunities. When properly executed, the urban and spatial transformation of post-mining sites may significantly enhance their visual and functional value. However, for quarries intended for public access, ensuring safe usage conditions is essential, thus making slope stability a critical design and management concern. This issue is particularly challenging due to the need to account for previous mining-induced disturbances, the integrity of the rock mass, and the long-term stability of the slopes. Furthermore, it is vital to minimise the risks associated with slope failures and rockfalls to protect the public and prevent potential injuries. The present study focuses on the former quarry of thick-bedded limestones with chert nodules, historically referred to as \"Twardowski's School\", and later redeveloped into Bednarski Park. Quarrying operations at this site date back to medieval times and officially ceased in 1884, although extraction in the southeastern section continued for a short period thereafter [1]. On 19 July 1896, the former quarry was officially transformed into a municipal park, subsequently named Bednarski Park. Given its current recreational and public functions, ensuring the geotechnical stability of the rock slopes is a fundamental requirement to guarantee safe long-term use and public access. Geological structures and joint systems are key factors influencing the stability and quality of rock masses [2; 3; 4; 5; 6; 7; 8; 9; 10; 11; 12; 13; 14; 15]. This research indicates that the orientation of geological joint sets reduces the rock mass strength, with steeply dipping features contributing most significantly to this effect [16; 17; 18; 19]. When multiple sets of discontinuities with varying orientations are present within the rock mass, their precise characterisation becomes crucial for assessing slope stability, as these features directly influence the potential failure mechanisms and loss of stability. Therefore, the accurate identification and reconstruction of joint orientations, as well as comprehensive characterisation, are fundamental for reliable rock slope stability analysis [15; 20; 21; 22; 23; 24]. At the same time, it is essential to recognise the substantial uncertainty involved in determining the joint parameters. Several authors have emphasised this issue [25], suggesting that confidence intervals should be assigned to discontinuity properties rather than using fixed numerical values. In numerical stability assessments, discontinuities are mostly considered indirectly by implementing the Hoek-Brown failure criterion for fractured rock masses [11; 19; 26; 27; 28; 29; 30; 31; 32; 33]. This approach treats the rock mass as a continuous medium with appropriately modified strength properties. When the Geological Strength Index (GSI) classification is applied, the parameters required for the Hoek-Brown criterion can be derived. These parameters are usually converted into Mohr-Coulomb parameters for practical calculations. However, such an approach does not account for the layered discontinuities or the specific orientations of joint systems. Consequently, while stability conditions may be assessed, the predicted failure mechanisms may differ significantly from those observed, particularly in terms of the actual geometry of the slip surface.