Eastern Region of Petroşani Depression is a complex intensely modified by coal mining activity, an activity that has increased the vulnerability of the system and the formation of critical environments which evolution over time is difficult to establish. Critical environments, seen as the product of environmental system malfunction caused by human intervention, takes the form of thresholds, characterized by phenomena of disorganization of information and energy that reduce or make disappear entirely the internal capacity of the system to self-regulate and to ensure a dynamic balance.