Monitored Natural Attenuation (MNA) and Enhanced Natural Attenuation (ENA) represent economically more feasible concepts as compared to classical soil and groundwater remediation techniques such as pump-and-treat. In Germany, at present concepts and strategies for the assessment of natural attenuation are developed.
In this interdisciplinary research project, the natural attenuation processes are studied in a chloroethene contaminated aquifer located in the river rhine valley. It is the objective of our project to examine in particular the microbial degradation processes. The results of microcosm studies will contribute to the reactive transport modelling of the plume.
At the Water Technology Center, the field samples are analysed with respect to the chlorinated pollutants (tetrachloroethene, trichloroethene), the biological degradation products (dichloroethene, vinyl chloride, ethene), and the electron acceptors and respiration products in the plume.
Biodegradation of the chloroethenes is studied in the presence of the relevant electron acceptors and after addition of auxiliary substrates. Furthermore, the effects of sediment material with high organic content and of well defined humic acids will be examined. The studies will improve the understanding of the factors limiting biodegradation in the field, and will show the potential to enhance the natural attenuation processes.
Funding priority KORA - Retention and Degradation Processes to Reduce Contaminants in Groundwater and Soil