Abstract

Groundwater polluted with complex mixtures of different pollutants constitutes a major threat to European groundwater resources. Permeable barrier technology is a sustainable in situ system to reduce risks associated with polluted water flowing in the direction of important groundwater resources. However, plumes polluted with pollutant mixtures are non-treatable using the currently available barrier technology. This project aims to develop and examine the feasibility of a Multifunctional Permeable Barrier (MULTIBARRIER) which combines different principles of barrier technology, namely the removal of pollutants based on both physico-chemical (zero valent iron for chemical reductive dechlorination/ sorbing materials) and biological activities (biofilm on MULTIBARRIER material) in order to treat mixed polluted plumes. The project foresees the development of the MULTIBARRIER from laboratory scale to pilot scale and includes the selective enrichment of specifically designed biofilm communities. Furthermore, it includes characterisation of the microbial populations involved, the (bio)chemical/ biological interactions taking place and the removal/degradation pathways of the pollutants.

Objectives

• To develop the MULTIBARRIER concept for treatment of mixed pollution on a laboratory scale up to the scale of a container pilot system and to evaluate the concept for field application.
• To select and find microbial populations suitable for the MULTIBARRIER technology.
• To optimise the performance of the MULTIBARRIER communities by adequately supplementing growth-promoting additives.
• To understand the interactions between the key-components (chemistry, biology, physics) of the MULTIBARRIER and define occurring physico-(bio)chemical xenobiotic removal/degradation pathways.
• To characterise and monitor the MULTIBARRIER microbial communities.
• To define a full-scale implementation strategy of a MULTIBARRIER.

Description of the work

The work is organised in seven Workpackages (WPs) and comprises 4 main parts.

Part 1 (WP1, WP2, WP5) includes the development of the MULTIBARRIER concept on a laboratory scale up to a pilot scale. In WP1, the compatibility of different key-components (the microbiology and the coarse material) to function in a MULTIBARRIER system will be examined in small-scale column systems by monitoring the removal of pollutants in a model mixed polluted groundwater. The activity of different microbial populations (endogenous and specific inoculants) will be assessed in the presence of different (reactive) coarse materials under a wide range of environmental conditions. Relevant growth-promoting additives for the microorganisms will be tested. In addition, specific well-performing microbial populations adapted to the MULTIBARRIER environment will be enriched. Thus WP1 will allow us to define compatible combinations of (reactive) coarse material and microbial input usable for the MULTIBARRIER technology and to define a set of promising MULTIBARRIER concepts. In WP2, the potential of the chosen MULTIBARRIER concepts will be studied and their activity will be optimised. The behavior of the pollutants, their degradation/precipitation products and of additives through the system will be monitored. In WP5, the best-performing MULTIBARRIER concept of WP2, will be chosen to be monitored in a container pilot scale system.

Part 2 (WP3, WP4) includes the microbial characterisation of well-performing MULTIBARRIER systems of Part 1 in order to understand the (bio)chemical, physical and microbial interactions taking place in the system. In WP3, the general microbial ecology and the biofilm communities present in well-performing MULTIBARRIER concepts of WP2 will be studied and related to MULTIBARRIER activities. WP4 foresees the detailed characterisation of bacterial isolates coming from the system.

In Part 3 (WP6) a technical implementation strategy of a full-scale MULTIBARRIER will be worked out.

Part 4 (WP7) foresees the management of the project and the development of a methodology for easy transfer of knowledge towards potential interested industrial and socio-economic entities.

Deliverables

• A well-performing MULTIBARRIER system on a laboratory scale and pilot scale (which can be used for on-site MULTIBARRIER treatability studies) with the capacity to treat groundwater containing mixed pollution.
• An implementation strategy protocol describing the environmental conditions and different steps to be taken into account to install and apply in situ a MULTIBARRIER system.
• A thorough understanding of the microbial, biochemical and physico-chemical interactions and of the pollutant removal pathways, taking place in the MULTIBARRIER system.

Contacts

Coordinator

• Ludo DIELS / Flemish Institute for Technological Research VITO - Environmental Technology / BELGIUM

Participant

• Biotecs Technologie für Technik und Umwelt GmbH i.G. GERMANY
• Klaus LIEFEITH / Institute for Bioprocessing and Analytical Measurement Techniques Rosenhof / GERMANY
• Katerina DEMNEROVA / Institute of Chemical Technology Prague Departent of Biochemistry and Microbiology / CZECH REPUBLIC
• Thomas PÜMPEL / Leopold-Franzens-Universität Microbiology Department / AUSTRIA
• Siegfried D'HAENE / Soils nv. BELGIUM
• Stefan WUERTZ / Technical University of Munich Institute of Water Quality Control / GERMANY
• Wageningen University Laboratory of Microbiology / NETHERLANDS