The long-term optimisation of mine water drainage is a central issue regarding which RAG Aktiengesellschaft, Essen/Germany, is facing up to its responsibility in the period after active coal mining has ended. The Ruhr region’s mine water plan envisages that mine water will only be raised at six central drainage sites. From 2030 onwards, the Lohberg site in Dinslaken will be the largest central water drainage system in North Rhine-Westphalia (Figure 1). Up to 33 M m3/a of water will be raised here and discharged directly into the Rhine river.
In an extensive feasibility study, RAG has demonstrated that raising mine water at the Lohberg site will, in all probability, be technically possible and that subsequent discharge into the Rhine river will be legally permissible. RAG’s mine water plan provides for various safety measures that are taken into account in the feasibility study. The feasibility study is a basic prerequisite for approving the outstanding colliery closure plans, in particular regarding the former Prosper-Haniel mine and withdrawing from the Zollverein, Amalie and Carolinenglück mine water drainage sites.
RAG’s mine water plan for the “water province” of Lohberg envisages discharging mine water directly into the Rhine river in the future. This means that the Emscher river will be completely cleared of mine water. This is a basic prerequisite for successfully completing the intergenerational Emscher conversion project. In this sense, the Lippe river will also be significantly relieved.
The plan also provides for a clear distance between the mine water and the groundwater resources used for drinking water production at all times and in the long term. This applies, in particular, to drinking water production from the Halterner Sande area, through which over 50 M m3/a of natural groundwater is currently extracted for drinking water supply. The mine water plan is thus primarily also a concept for drinking water protection. (RAG/Si.)