IWRA Proceedings

Inflows of subterranean waters into mine workings during the exploitation of various types of mineral raw materials have been known since ancient times1 . Inflows of subterranean waters frequently prevented the continuation of deposit exploitation due to the highly primitive drainage conditions. The development of technology and drainage equipment has meant that mine drainage problems have stopped constituting a determining factor with regard to the possibilities relating to the opening out and production of particular raw materials. The ability to carry off natural subterranean waters flowing into mine workings has however not eliminated the problem connected with water hazards, which generally arise in circumstances where drainage measures have not been adapted to take into account hydrogeological conditions that have been insufficiently identified. The issues linked with water hazards are not the subject of the present discussion, although the discussed technology, which limits the inflows of subterranean waters into mineral raw material mines has a direct impact on eliminating them.

Currently inflows of subterranean waters into mine workings considerably increase the deposit exploitation costs and have a negative environmental impact due to the effect of the funnel shaped depression that arises on the surface. The ever more stringent environmental protection regulations mean that this issue also has an economic dimension. In light of both of these factors attempts to mine new mineral raw material deposits bring about considerable doubts with regard to their profitability due to economic factors and the environmental hazards which are difficult to predict accurately. A factor favouring sealing of aquiferous levels for the purposes of the mining industry is the considerable progress that has been achieved over the last twenty years with regard to the production of all types of relatively cheap sealing components and solutions.

Freezing the rock mass constitutes a highly effective, although also very expensive sealing process. This is a temporary measure and is generally only carried out over a limited segment of specific mine workings (shafts, tunnels) and encompasses a whole block of pervious and impervious aquiferous layers. This system that has been known and applied for years is not the subject of the present discussion.

The sealing method presented here based on various types of binding materials constitutes a permanent solution for given mine workings or even for an entire mine and it is characterised by the precise selection of specific aquiferous levels and layers based on the natural conditions of their deposition and tectonic engagement.