Estonian oil shale has been used for 90 years mainly for electricity and oil generation with the ash being used for cement and light brick production. The oil shale usage has always been related to available mining and processing technology, and vice versa, with external influences of worldwide petroleum prices. The same situation is true today, when new technology is being applied in power generation units, in oil generators and in oil shale extracting processes.

The paper introduces a high-selective oil-shale mining technology and the first results of surface miner Wirtgen 2500SM tests. The technology allows to decrease oil-shale loses from 10-15% up to 5-7%. Mining process of the surface miner has a lower disturbing impact, which is topical in open pits and quarries especially in densely populated areas. The low level of dust and noise emissions and also very’ low vibration are arguments to mine oil shale with surface miner instead of drilling-blasting operations. The risk analysis for testing technology was elaborated.

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The paper deals with risk management problems in Estonian oil shale mines. Investigations are focused on application of the method to determination of the quality of geological data. Various factors relevant to mining technology in Estonian oil shale deposit have been determined. For risk estimation, the empirical and judgmental approaches and the event tree were used. They allow determining the probability of the occurrence of geological features and its influence on the mining process. Analysis of obtained results showed that it is necessary to elaborate special methods for determination of the geological conditions in the mining area. The obtained information affords specialists to improve the quality of geological information and consequently the mine work efficiency. The analysis shows that the used method is applicable in conditions of Estonian oil shale industry. The results of the investigation are of particular interest for practical purposes.

Surface miners (further SM) can find their natural applications in projects where drilling and blasting is prohibited or where high-selective mining of mineral seams required. Selective mining improves the quality of oil shale. Through the cutting quality the mineral resource utilisation is more effective and environmental impact is lower. The present paper introduces a highly selective oil-shale mining technology and results of an analysis on cutting and quality parameters. Size distribution and calorific value of oil shale is in dependence on cutting thickness and cutting (advance) speed. It is possible to achieve required average size of mined oil-shale particles, which was confirmed by the present investigation data. The information obtained enables specialists to improve the quality of mining works by means of fuel consumption optimisation.