GEOLOGICAL ASPECTS OF RISK MANAGEMENT IN OIL SHALE MINING Jüri-Rivaldo Pastarus, Katrin Erg and Sergei Sabanov Tallinn University of Technology, Department of Mining Erik Väli, Oleg Nikitin and Tarmo Tohver Estonian Oil Shale Mining Company, AS Eesti Põlevkivi

Objective To evaluate the usability of the risk assessment / management methodology in oil shale mining To estimate the pobability of geological aspects

Oil shale mining in NE Estonia

Geology

Room-and-pillar mining

Open cast mining

Risk assessment / management process

Probability estimation Analytical approach Uses logical models for calculating probabilities Empirical approach Uses existing databases to generate probability Judgmental approach Uses experience of practicing engineers

Geological and technological aspects of underground mining

Event tree

Collapse of immediate roof Acceptable risk level is 1 x 10-3… 1 x 10-2

Collapses

Collapses

Collapses

Conclusions Risk management method allows to predict probability of the geological feature at the interested location. Receipt of information allows specialists to mitigate negative influence on the excavation process and environment

Acknowledgment Estonian Science Foundation (Grant #6558, 2006 – 2009) supported the research Thank you for your attention!