2011 - 2014

The capillary fringe is a highly active zone for chemical and biochemical transformation. Due to the broad

abundance of synthetic organic micropollutants it is a basic question with high ecological significance

how these substances behave in the unsaturated and saturated zone, and how these substances are

biodegradable. The possible transformation of the pollutants and the integration of their metabolites

into the biogeogenic organic matrix (bound residues) is fundamental but not well understood. It can be

expected that the fringe zone with its bioactivity will be highly active for degradation and transformation of

substances. The main objective of this project is to study mass transfer and biological transformation of

organic compounds across the capillary fringe. Relevant processes and the main parameters influencing

the reactions will be quantified. By this, studies in a 2D-tank (horizontal and vertical flow), column (vertical

flow) and batch (diffusion) experiments will be performed. Mass transfer of the compounds of interest

(phenol, salicylic acid, benzene sulfonic acid, X-ray contrast media and atrazine) will be measured as a

function of horizontal flow velocity of the water, water table fluctuation amplitude and frequency, variable

infiltration flux, composition of the aqueous phase (high and low ionic strength, NOM concentration) and

the bioactivity of the fringe zone.

• UFZ Leipzig/Halle, Prof. Dr. H.-J. Vogel/Prof. Dr. H. Geistlinger, Department of Soil Physics/ Environmental Simulation and Modelling, Leipzig/Halle
• University of Heidelberg, Interdisziplinäres Zentrum für Wissenschaftliches Rechnen, Prof. Dr. P. Bastian, Dr. O. Ippisch
• University of Tübingen, Zentrum für Angewandte Geowissenschaften, Prof. Dr. P. Grathwohl
• Karslruher Institut für Technologie, Institut für Ingenieurbiologie und Biotechnologie des Abwassers, Prof. Dr. J. Winter, PD. Dr. C. Gallert (Coordination)