Analysis of the hazards of the BAZALY football stadium in Ostrava in terms of environmental impact

Abstract

The term »geohazard« is used to describe the natural and anthropogenic phenomena and processes taking place in the natural environment in the context of their negative influence on natural environment, including the geological one. The degree of geohazard is frequently evaluated on the basis of catalogued descriptions (activity of natural environment and human impact), which help identify particular hazards and ascribe them their value. According to Czech standards, 45 geohazards have been classified and described in detail in view of: geological knowledge, origin and way in which the hazard was evoked, geographical range, time, associated processes, social aspect and monitoring methods. Research works were conducted in a football stadium located in an area of underground hard coal extraction and surface production of raw minerals. The BAZALY stadium, where FC Banik Ostrava played its matches, is located in Ostrava in an area of former mining fields of Silesian Ostrava. These coal mines were closed in the 1990s, but even so they still create environmental hazards. The paper is devoted to research works and risk analysis of the environmental impact of mining activities, old workings and liquidated mines in terms of geohazard. The basic geohazard in the stadium area is methane migration from tectonically disturbed rock mass, also caused by incorrectly closed workings. Another hazard is associated with the increasing mining damage, i.e. tectonic movements, subsidence, local sinkholes, lowering groundwater level etc.