We offer a new technology to immobilize contaminants in-situ which is based on long-term investigations of the kinetic processes of precipitation and crystallisation. Heavy metals are bind or transferred to insoluble compounds. Oversaturated solutions are used and slightly soluble minerals are formed. Simultaneously reactive mineral surfaces (sulphides) can be layered with slightly soluble minerals for a long time.

Solutions can be prepared to get gypsum (CaSO4*2H2O), BaSO4, CaCO3 or Ca(OH)2. All systems can transfer contaminants into non-easily dissoluble and long-term resistant compounds by adjusting pH, redox potential and oversaturation. Natural running processes of contaminant fixation and reduction of permeability are reproduced.

Substantially natural occurring minerals are used and the application of non-natural materials is avoided.  At the moment we are working on a plenty of investigations of contaminant fixation by directed sulphide precipitation. The transfer of laboratory tests into field tests will take place during the next months. One of our reference projects was successfully deployed in the mine of Königsstein which belongs to Wismut GmbH.