Identification and analysis of geotechnical risks in the conditions of flooding of the remaining gaps

Abstract

Controlled flooding of the remaining gaps of former quarries (especially lignite quarries) and the formation of lakes that can take different uses is one of the ways of recovering and rehabilitating degraded mining lands which offer opportunities for sustainable development of a mining region. The advantages of such a solution are multiple, starting from the restoration of biodiversity, to economic and social benefits. Basically, several flooding techniques are known, but depending on the geological, geotechnical, hydrological and hydrogeological conditions characteristic for a particular region, these techniques must be adapted to the risks that may arise before, during and after flooding the remaining gap. Most of the times, the risks are of geotechnical nature and arise as a result of the interaction between the rocks and the mixture of loose rocks that form the final slopes and the dump with water. The paper is part of an extensive research, which is carried out under the concrete conditions of the remaining gaps in the Rovinari mining basin, and essentially aims at: identifying the main categories of geotechnical risks that can occur under the given conditions, determining the triggering factors, to produce negative geotechnical phenomena and their effects, as well as to identify the main measures to avoid them.

Reassessment of the Stability Conditions in the Lignite Open Pits of Oltenia (Romania) in Relation to the New Local Seismic Context as an Imperative for Sustainable Mining

“…In order to highlight the influence that seismic movements in the Oltenia mining region can have on the stability of the mining works in the three studied perimeters, we considered several previous studies, conducted by the authors and their collaborators [1,2,38,41,[59][60][61].…”

A Model to Evaluate the Flooding Opportunity and Sustainable Use of Former Open-Pits

“…Water quality varies among pit lakes due to geological and hydrogeological conditions. In many cases the lake water is toxic, containing a high concentration of heavy metals, acidic or saline, posing risks to adjacent communities and ecosystems, while in other cases the lake contains fresh and clean water [4][5][6][7][8][9]. Besides the water quality, which is an important aspect when planning the reuse of the pit lake, the geotechnical risk arises.…”

“…Besides the water quality, which is an important aspect when planning the reuse of the pit lake, the geotechnical risk arises. The geotechnical risks refer to hazards such as landslides, which may have major impacts on the environment and local communities [5,[8][9][10][11][12].…”

Analysis of liquefaction risk of sterile material in the inner dump of North Pesteana quarry in the conditions of flooding of the remaining gap

“…Vibrations caused by earthquakes, explosions, heavy vehicles, ground and underground traffic, and seismic shocks during earthquakes can also influence this phenomenon. [2] Examples of liquefaction phenomena can be given at European level. Germany is one of the countries that has encountered numerous liquefaction problems (exmples Laubusch (1962), Lippen Nord (1984), Skado (1984), Sedlitz (1987) și Lohsa II (1995) mining exploitation), but it is also one of the best examples of good practices of rehabilitation of areas affected by liquefaction.…”