The construction of underground waterproofing systems has its specifics due to the requirements to ensure an extremely long service life, and due to the direct chemical impact to which the materials used are subjected.
Upon the waterproofing properties compromising, its repair is in many cases practically impossible due to the difficulty to provide access to the system. This applies especially to a number of special facilities – drinking or industrial water tanks, fire-safety systems, landfills, tailings ponds, etc.
The choice of suitable material is of particular importance for the overall reliability of the system. Underground waterproofing is subjected to continuous impact of water, which requires increased water resistance of the materials used. In practice, it happens that the underground waterproofing system is also exposed to the chemical effects of harmful substances such as industrial water, petroleum products or mineralized groundwater. In these cases, the use of some waterproofing materials – polymer and bitumen-based – is not recommended. The materials must also be biologically stable, as there is access of oxygen in the wetted areas and redox processes take place.