Variations in the building site categories in the underground mining region of Doubrava (Czech Republic) for land use planning

In terms of demands and needs of ground investigation and foundation engineering, the engineering-geological conditions in the underground mining territories represent anthropogenically influenced areas in the most complicated manner, since they suffer the impacts from the underground mining of mineral resources. The subjects of observation are the so-called building site categories, which represent a certain risk factor that must be taken into consideration during foundation engineering and engineering-geological studies in the undermined territories. It is necessary to realise that underground mining is an anthropogenic geodynamic process which significantly varies over time due to mining change, and consequently with variations in the position, shape and size of subsidence in a subsidence basin. All the above mentioned variations should be mandatory knowledge for land use planners, engineering geologists, geotechnicians, foundation engineers and designers because of the evident logicality of these needs. This work presents a case study (Ostrava-Karvina Coal District in the north-east of the Czech Republic) of variations in the building site categories over time, and the results show that the chronology of the changes has a very significant influence in this area of interest. The results of the building site category evaluation imply that the majority of the interest area falls within relatively good conditions for founding all kinds of structures. However, it was then necessary to consider variations over time in the surface area of less suitable building site categories. A trend certainly confirmed the existence of the previously presumed mutual relationship between building site categories and subsidence size distribution. It is apparent from the analytic results of the relationship between building site categories and planned development that the negative impacts of mining have been only partly considered, or completely disregarded, in the development planning process. Consequently, future land use planners should carefully consider these particular building site categories as the most important and significant factors in the undermining of a region. In this manner, development can be successfully planned for present and future safety.