In the future, oil shale mining conditions will worsen and environmental taxes will be increased. Higher calorific value and more homogeneous material are required for more effective usage of boilers and generator units in power stations and oil plants. The solution for the mining industry is related to the optimal usage of mineral and technological resources, utilizing the best available techniques and modelling and visualization of mining impacts for explaining the changes in technology to the influenced parties. The main challenges for technologies in the future are related to the mining in environmentally or socially sensitive areas. One of the solutions could be utilizing selective mining and backfilling. Related tests have shown good results and show a promising future for sustainable oil shale mining.

The basic parameters of oil shale quality are heating value and grain-size composition. Heating value can vary considerably within the location in a deposit and depends on concretions and limestone content. Grain-size distribution and heating value depend directly on mining technology: breakage, transporting and processing. Energy distribution when using different technologies was determined. New boilers of oil shale power plants and oil retorts require a relatively constant quality of raw materials and fuel. The possibility of improving oil shale separation was investigated.

The research needed for sustainable mining should be performed in nature, but large-scale tests are complicated. These studies are performed by computer modelling. The main task for modelling is to find suitable criteria and demonstration ways. Modelling is a relatively new approach for planning new mines and analysing abandoned ones. Modelling itself is a convenient way for choosing, selecting and visualising the results, but deciding about optimal modelling methods and software is a complicated task. There are three main tasks of modelling to solve: mining technology, planning and development of mining and impact of mining.

Underground oil shale mining has been applied for ninety years inEstonian deposit in the middle-north part of Baltic oil shale deposit. The underground mining method of oil shale creates underground free space and the mine workings are filled with water after closure, which makes issues of land stability topical.Underground water pools or technogenic water bodies with all-the-yearround stable temperature are formed in the filled underground of oil shale mines. These water bodies have a potential for use as a source of heat for heat pumps and reduction of wintertime heating costs. The aim of this research is to calculate the amount of mine water in closed or abandoned oil shale mines in the central part of Estonian oil shale deposit and offer solutions for usage of undermined areas.Using mine water as a source of heat for heat pump stations means the possibility of using geothermal energy. The first pilot pump in Estonia was launched in Kiikla settlement in 2011. The best solution for such systems is a heat pump complex near Ahtme thermal power plant. The optimal size for the heat pump at Ahtme is 10 MW heat production. Different methods of heat collection for heat pump plants can be applied when other mines will be closed in the future.A 3D-model of the mined underground area has been created using geometric data of mine plans, acts of closed mines, as well as borehole and land survey data. The main tools chosen for spatial modelling were spreadsheets and Microsoft Access databases for systemising and querying data, MapInfo Professional for georeferencing, Vertical Mapper for interpolating and grid calculations and MODFLOW for pumping simulation. Each step of model creation involved analysis and decision on which values should be used to obtain modelling results. Layer thicknesses and required properties of water body were calculated using interpolated grids and surface elevations.

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