Prof. Christof Holliger, Dr. Pierre Rossi, Dr. Sonia Tarnawski
Technology Agency of the Czech Republic and Swiss Federal Office for Environment
May 2012 – December 2015
Dr. Maria Brennerova, Institute of Microbiology, Prague, Czech Republic; Dr. Ing. Monika Stavělová, AECOM CZ, Prague, Czech Republic; Dr. Ing. Tomáš Lederer, Aquatest a.s., Prague, Czech Republic; Ing. Jiří Mikeš, EPS s.r.o., Kunovice, Czech Republic; Radek Heřmánek, KHSanace s.r.o., Prague, Czech Republic; Dr. Ing. Miroslav Černík, Technical University of Liberec, Czech Republic; Pavlína Hlaváčová, VODNÍ ZDROJE a.s., Prague, Czech Republic; Dr. Jürgen Abrecht, Geotest AG, Zollikofen, Switzerland
Reductive dehalogenation of chlorinated ethenes to the non-toxic end-products ethene and ethane is used for nearly 20 years and it is considered for the most efficient and frequently used remediation method. However, in some localities the initially successful transformation is halted at cis-DCE and carcinogenic VC, and the reason for the incomplete reduction are often unknown. The main objective of the project is therefore to design, test and verify a technology for assessment and support of the complete elimination of chlorinated ethenes from groundwater. Additional output from the research activities will be the use of a novel molecular biology approach in exploring of the reductive dehalogenation of chlorinated ethenes during remediation activities and establishing of a multidisciplinary evaluation table with key parameters and values which can help to predict a stagnant or complete reductive dehalogenation. The criteria table could serve as an easy guide for remediation companies and will be a helpful directive for control authorities and state administration during evaluation of the remediation efficiency.
The final result of this project was a methodological report entitled “Screening of the bacterial reductive dechlorination potential of chlorinated ethenes in contaminated aquifers”. This report is presented as a technical assistance manual for assessment of natural attenuation of chloroethenes (CEs) contaminated sites using a 3 steps screening tool. Briefly, the first step of the approach is devoted to acquisition of the key physicochemical data of the studied aquifer. The second step concerns the characterization of microbiology directly and specifically involved in the reductive dechlorination of CEs (levels of populations, activity of cells and functional genes). The third step completes the analysis of microbiology at a wider scale (communities) that includes not only reductive dechlorination but all bacterial activities of the aquifer. This last step also provides a MFA statistical analysis integrating microbiology and physicochemistry inquiries to assess the global biogeochemical characteristics of the aquifer and their impact upon the reductive dechlorination potential of CEs.