ENACT Extending the Monitored Natural Attenuation Toolbox for Chlorinated Solvents

Country: European Union
Start Date:   27/11/2007         Duration: 12 months         Project Type: RTD
Contract Number: SN-01/24
Organisation Type:  Consultancy, contractor or other service provider
Contaminated land-->Contaminants-->Contaminants overview
Contaminated land-->Contaminated land overview
Groundwater protection-->Groundwater processes-->Groundwater processes overview
Groundwater protection-->Groundwater protection overview
Soil-->Soil Overview
Project objectives:
The presence of harmful chlorinated substances in the subsurface    
is a large threat to our groundwater reserves. Fortunately, nature    
has found several ways to destroy these compounds. In the subsurface,    
both biological and chemical processes may occur that cause    
degradation to non-toxic end products. This is called natural attenuation    
or NA. Some of these NA processes are well-known and    
can be demonstrated rather easily. For other processes that can potentially    
play an important role, it is more difficult to find evidence.    
Traditional methods are not suited for demonstrating these processes    
and their significance in the subsurface is still unknown.    
In this project, we investigate the use of a new analytical technique    
called “compound specific stable isotope analysis (CSIA)” to study    
the relevance of the abovementioned NA processes. With CSIA, we    
can study the properties of single atoms in the contaminant molecules.    
Chlorinated solvents consist of carbon and chlorine. By looking    
into both types of atoms, it is possible to identify and quantify    
different NA processes. CSIA for carbon is already applicable for    
field application, but CSIA for chlorine has been developed very recently    
and requires optimization.    
The objective of the project is to optimize the use of CSIA for chlorine    
and to demonstrate the use of combined carbon and chlorine    
isotope analysis at tool for demonstrating natural attenuation of    
chlorinated solvents. 
Project Summary:
At the institute WAR of the Technical University of Darmstadt in    
Germany, the method for stable chlorine isotope analysis will be optimized    
to make it suitable for application on samples from contaminated    
groundwater. At the same time, a laboratory study will be performed    
at VITO in Belgium, in which the relation between the targeted    
degradation processes and the isotope analysis results will be    
Since the results of the isotope analyses from field sites are difficult    
to interpret and to explain, an existing computer model suitable for    
interpreting carbon isotope data will be extended to make it applicable    
to chlorine isotopes.    
In the next phase, the method will be applied at three field sites contaminated with chlorinated solvents. At the same time, more conventional methods will 
be applied to obtain a complete picture on the natural processes. The site data will be interpreted using the developed computer model. The results from this project will help us to understand the complex natural processes that determine the fate of this class of harmful groundwater contaminants.
Achieved Objectives:

Product Descriptions:

Additional Information:

Project Resources:
Funding Programme(s): 
SNOWMAN coordinated Call
Link to Organisations:

Darmstadt University of Technology
National Research Center for Environment and Health
Built Environment and Geosciences Subsurfaces and Groundwater
Vrije Universiteit Amsterdam
Submitted by: Mr Arnd Wieland  Who does what?  10/01/2008 13:10:00
Updated by: Mr Arnd Wieland  Who does what?  10/01/2008 13:58:00