The chemical characterisation of the rivers, lakes and the groundwater are either supervised by public authorities, or monitored systematically by the LMBV. Depending on the problem discussed, the mining lake is spatially discretized from a 0-D mixing reactor to a fully 3-D representation. Long-term monitoring indicates, however, that the abstraction level of a 0-D mixing reactor is entirely sufficient. Besides the chemistry of rivers and the flood water, other aspects, such as additional input of substances through precipitation and wave erosion along the bank slopes, gaseous exchange between lake and atmosphere, and interactions with the sediments, are taken into consideration. The complex homogenous and heterogenous hydrogeochemical processes that take place in the lake (i.e., dissociation, complex formation, hydrolysis, precipitation and dilution reactions) are calculated by means of PHREEQC [Parkhurst&Appelo]. The predictions obtained are highly reliable, since the models are calibrated to the data obtained by the monitoring. The calibrated hydrochemical models of the lake eventually serve as basis for complex management models. (To the left)
Applied hydrogeochemical modelling: water quality in open-pit lakes
The prediction of the water quality in emerging open-pit lakes in the Lusatia region is conducted according to the principle of mass balance. The flow rate of rivers, of flood water, and of groundwater are determined by hydrological and geohydraulic modelling (e.g. WBalMo, PCGEOFIM) as well as through systematic monitoring.