Feasibility and Performance of Full-Scale In-situ Remediation of TCE by ERD in Clay Tills

Mette Martina Broholm, Ida Damgaard, Julie Claire Claudia Chambon, Gabriele Manoli, Dorte Moon Pade, Camilla Maymann Christiansen, Philip John Binning, Claus Westergaard, Aikaterini Tsitonaki, Mette Christophersen, Henriette Kerrn-Jespersen, Poul Løgstrup Bjerg

Research output: Contribution to conferencePaperResearchpeer-review

Abstract

The feasibility and performance of full-scale applications of ERD in clay tills were investigated in a research project including 2 sites in Denmark, which have been undergoing remediation since 2006. At both sites organic substrates and bioaugmentation cultures have been injected in TCE-contaminated clay till. An integrated investigative approach consisting of water and clay core sample analysis, including stable isotopes and specific degraders, as well as analysis for chlorinated solvents, degradation products, donor fermentation products and redox-sensitive parameters combined with modelling has been applied. The results showed that the chlorinated solvent TCE was converted into its daughter products (cDCE, VC and ethene) but complete conversion of contaminants to ethene (as expected) was not achieved within a timeframe of 4 years. Large variation in the effect of ERD in the clay matrix between sites, boreholes and even between cores was observed. Four years post ERD initiation, the mass removal at the 2 sites varied between <5% and 50% within the treated zones. Low mass removal was associated with degradation being restricted to narrow bioactive zones (few cm) around high permeability features in some parts of the clay tills. The bioactive zones may expand in zones where both donor and chlorinated compounds are present. In some cores TCE was
depleted (degraded to DCE) in zones up to 1.8 m thick – an extent which could not be explained by diffusive loss to narrow bioactive zones. Hence, biomass migration in the clay matrix appears to play an important role in terms of contaminant mass reduction.
Original languageEnglish
Publication date2012
Number of pages8
Publication statusPublished - 2012
EventInternational Conference on Advanced Environmental Science and Technology (AEST12) - Seoul, Korea, Republic of
Duration: 26 Aug 201230 Aug 2012

Conference

ConferenceInternational Conference on Advanced Environmental Science and Technology (AEST12)
CountryKorea, Republic of
CitySeoul
Period26/08/201230/08/2012

Cite this

Broholm, M. M., Damgaard, I., Chambon, J. C. C., Manoli, G., Pade, D. M., Christiansen, C. M., Binning, P. J., Westergaard, C., Tsitonaki, A., Christophersen, M., Kerrn-Jespersen, H., & Bjerg, P. L. (2012). Feasibility and Performance of Full-Scale In-situ Remediation of TCE by ERD in Clay Tills. Paper presented at International Conference on Advanced Environmental Science and Technology (AEST12), Seoul, Korea, Republic of.