report of the nicole workshop - nicole network for ... · the nicole network meeting on 25-27 may...

REPORT OF THE NICOLE WORKSHOP: Operating windows for site characterisation

25-27 May 2011

Copenhagen, Denmark

www.nicole.org

Compiled by Elze-Lia Visser, secretary NICOLE Service Providers Group and Hans-Peter Koschitzky, academic member NICOLE Steering Group

http://www.nicole.org/�

Report of the NICOLE WORKSHOP: Operating windows for site characterisation

Acknowledgements

NICOLE gratefully acknowledges

• Grontmij for co organising the event • The speakers and chairpersons for their contributions to the meeting and their comments on this

report • The members of the Organising Committee:

o Kristian Kirkebjerg, Grontmij, Denmark / chair Organising Committee o Lucia Buvé, UMICORE, Belgium o Wouter Gevaerts, Arcadis, Belgium o Hans-Peter Koschitzky, VEGAS/University Stuttgart, Germany o Sarah MacKay, WSP, UK o Carla Schön, Electrolux, Sweden o Mark Travers, Environ, France o Elze-Lia Visser-Westerweele, NICOLE Service Providers Group, NL

• The NICOLE secretariats

NICOLE is a network for the stimulation, dissemination and exchange of knowledge about all aspects of industrially contaminated land. Its 120 members of 20 European countries come from industrial companies and trade organisations (problem holders), service providers/ technology developers, universities and independent research organisations (problem solvers) and governmental organisations (policy makers). The network started in February 1996 as a concerted action under the 4th Framework Programme of the European Community. Since February 1999 NICOLE has been self supporting and is financed by the fees of its members. More about NICOLE on www.nicole.org



Contents

1. Background 4

2. Strategies for characterisation 5 2.1. Make a conceptual site model ............................................................................................. 5

2.2. Geophysics ........................................................................................................................... 5

2.3. Non destructive field screening methods ............................................................................ 5

2.4. Risk assessment volatile contaminants .............................................................................. 5

3. Field techniques 6 3.1. Purge and no-purge groundwater sampling ......................................................................... 6

3.2. Sampling material in stockpiles ........................................................................................... 6

3.3. Sampling in door air ............................................................................................................. 6

3.4. Mass discharge from DNAPL zones ..................................................................................... 6

3.5. Direct push techniques ........................................................................................................ 7

4. Isotope analysis and DNA-analysis 8 4.1. Isotopes ................................................................................................................................ 8

4.2. Natural attenuation of MTBE ............................................................................................... 8

4.3. Biotraps ................................................................................................................................ 8

5. Forensics 9 5.1. State of the art ..................................................................................................................... 9

5.2. Pharmaceuticals .................................................................................................................. 9

5.3. Tree sampling ....................................................................................................................... 9

6. Overall conclusions and recommendations 10 6.1. General conclusions ........................................................................................................... 10

6.2. Recommendations ............................................................................................................. 10

Appendix 1. List of participants NICOLE Network Meeting on 24-27 May 2011, Copenhagen, Denmark 11

Appendix 2 List of speakers NICOLE Network Meeting on 24-27 May 2011, Copenhagen, Denmark and provided links for more information on the subjects 13

Appendix 3. Collated abstracts provided by speakers NICOLE Network Meeting on 24-27 May 2011, Copenhagen, Denmark 14


1. Background

The NICOLE Network Meeting on 25-27 May 2011 explored the subject of Site Characterisation Tools, and updated us on where they can provide value in the management of contaminated sites. We have all heard anecdotally, or may have tried some of the myriad of new techniques and approaches being proposed around the industry. From forensics using isotopes and DNA, to new drilling methods and microbes - the range of options on offer may seem confusing. From the ongoing work with the Soil Directive it is evident that some sort of baseline and monitoring will be needed in the future and we find ourselves facing other new pieces of legislation such as the Industrial Emissions Directive (IED) which may also have potentially onerous baseline monitoring requirements. As such, our thoughts turn to the tools and methods we have for investigation, and thought it was time to update ourselves with a state of the art review. This meeting has drawn us away from the marketing literature and technique sellers, and via a walk through the site conceptual model, explored and contextualised techniques appropriateness – for example:

• What technical conditions does it operate under – for example under what lithological or hydrogeological conditions can it actually operate and what are its limitations and ranges?

• In what circumstances will it add value - so for example is it only really warranted in a detailed compliance defence, or will it help to speed up development or remediation?

A programme of invited speakers reviewed the current and recent techniques and possibilities for site investigations such as drilling, sampling, in situ measurement and analysis for liquid, solid or gaseous contaminants in the subsurface. Moreover tracer tests, geophysics and last but not least plants as a pollutant diagnostic tool have been addressed. An entire days session was devoted to the development of advanced diagnostic techniques looking at forensics, DNA, isotopes, microbes, pharmaceuticals, and exploring some of the challenges in the analysis and the applicability both in corporate compliance work, and in remediation. The speakers explored the operating windows of the current and developing methods. The invited speakers presented lots of case studies also, showing where techniques are useful, applicable, appropriate and value for money. In this report you will find the conclusions of the Network meeting organised via 4 themes:

1. Strategies for characterisation. 2. Field techniques. 3. Isotope analysis and DNA-analysis. 4. Forensics.

On each theme you will find a list of conclusions drawn from the different presentations in the NICOLE Workshop. In the appendix of this report the abstracts that have been provided by the speakers have been collated. From the NICOLE website www.nicole.org the presentations and the programme of the meeting can be downloaded. For further information on the presentations you can approach the speakers, their contact information is listed in the appendix to this report. This report reflects the conclusions of the NICOLE Workshop and the outcome of discussions. This document doesn't necessarily reflect the opinion of NICOLE and/or individual NICOLE members or member organisations.



2. Strategies for characterisation 2.1. Make a conceptual site model

• Heterogeneity in the soil must be taken into account in conceptualizing your site model. • Work from macro scale into micro scale • Choice of technologies for conceptualizing your situation is not “either … or ….” but “….and…..”. • Take all results into account and try to visualize into a conceptual site model via an integrated

approach. • It all starts with understanding geology….. • Key issue for all steps to follow is to develop and understand the conceptual site model.

2.2. Geophysics

• Different geophysical methods can be used before drilling to visualize (to get an idea of) soil properties.

• Can in some specific cases be used for imaging contamination (DNAPL source zones in specific situations), use with care and be aware of robustness of the (imaging) tools.

• In case of use for imagining contamination: additional information is always needed for interpretation. Inform yourself on the limitations of the specific methods.

• Can in some cases also be used for monitoring progress in remediation.

2.3. Non destructive field screening methods

• Non destructive methods can guide traditional sampling and as such optimize site investigation strategies (drilling campaigns, prioritization of investigation).

• Non destructive techniques can be divided in screening techniques (e.g. XRF, MIP, PID) and geophysical techniques (e.g.GPR, EM, Medusa).

• Can be quick method for determining the scale and boundaries of contamination.

2.4. Risk assessment volatile contaminants

• Risk assessment of contaminated soil vapour intrusion for existing buildings can be done by measurements; for new (to be developed) buildings modelling is the way of working; a lack of reliable parameters often causes a gap in necessary information.

• Models exist and differ from each other on used parameters and type of transport of the contaminant and give a large range of results.

• Choose your model site specifically. • Communication on risk assessment needs attention.


3. Field techniques 3.1. Purge and no-purge groundwater sampling

• No purge sampling with Passive Diffusion Bags and Hydrosleeves has been tested in practice. • No purge sampling can effectively be used for long term monitoring. • No purge sampling can significantly differ from purged sampling, especially in low permeable

zones and DNAPL zones. • No purge sampling can give a better insight into the distribution of the contamination. • Based on the results the interpretation can be that in source zones passive sampling (no purge)

should be used for risk assessment instead of purged sampling: purging can mobilize free phase droplets (interpretation, not proven yet).

• In source zones purged sampling is to be used for remediation design. • In plume zones (dissolved concentrations) either technique will work. • More case studies are needed. • Based on the significance of the results and the consequences they could have in practice

investigation under controlled conditions (large scale in lab) is recommended.

3.2. Sampling material in stockpiles

• Sampling covers a wide field, two examples have been worked out on sampling granular material in stockpiles.

• Way of sampling adds to (un)certainty to results. • Validation of the samples itself in practice is not feasible due to the huge amount of cost. • Lot of work has been reported in international standards. • Work in progress on decision support tool for reliable sampling. • Numerical tools / concepts may be useful for interpretation data from groundwater / soil

sampling.

3.3. Sampling in door air

• Indoor sampling of in door air is affected by many factors: weather, geology, building properties, characteristics of the pollutant and others.

• Risk assessment has to be based on average concentrations which needs measurements of indoor air over a longer period of time

• Several devices (more or less mobile) are available to do measurements during a short or longer period of time

3.4. Mass discharge from DNAPL zones

• Evaluating planes and mass discharge instead of point measurements is an effective way of characterizing the contamination and monitoring remediation.

• Reliable methods for quantification of mass discharge exist. • Multi level sampling methods are needed to evaluate mass discharge in a control plane. • Hydraulic conductivity is the main parameter influencing mass discharge calculations. • Evaluation of the effective number of sampling wells related to the value of the mass discharge

is subject to optimisation to save money and time. • Uncertainty analysis of mass discharge is an important area for further development.


3.5. Direct push techniques

• Can be used additionally to or instead of traditional sampling and is cost-efficient. • Direct push technologies are very suitable for applying dynamic work plans. • Give fast results that can be transformed into immediate action for further data acquisition,

sampling or monitoring and remedial installations. • Some Direct Push techniques are based on indirect measurements (parameters). These indirect

measurements need to be calibrated with respect to the parameters of interest. • Be careful in using equipment in multilayered aquifers: do not penetrate a sealing layer below a

contamination to avoid cross contamination or worse creating spreading of contaminants in a less or not contaminated aquifer (which is also valid for every drilling).

• It should always be considered that the sealing of the probing holes for some Direct Push techniques are difficult or even not feasible.

• A well-versed team is a requirement for its reliable application and for the interpretation of the data.


4. Isotope analysis and DNA-analysis 4.1. Isotopes

• Isotope analysis is a powerful tool to evaluate natural and/or enhanced biodegradation of different contaminants (proof of degradation and degradation rates).

• Isotopes are sensitive parameters and experience is needed to be able to evaluate the outcome.

• Isotopes can be used to identify (additional) sources of contamination. • Isotopes can be used to conceptualize your site model (e.g. flow paths, degradation pathways)

4.2. Natural attenuation of MTBE

• Compound specific stable Isotope analysis (C and H isotopes) combined with DNA detection of key enzymes can provide quick and direct information on degradation of MTBE (potential for degradation, chemical or biological degradation, actual or historical degradation, degradation rate).

• Molecular techniques (DNA and RNA) can be used to detect the presence or activity of MTBE degrading bacteria.

• Outcome of isotope analysis and DNA detection needs validation with batch data and field data from contaminated site.

4.3. Biotraps

• Biotraps are a passive sampling tool that collects microbes over time and mimics the environmental conditions in the soil.

• Biotraps loaded with labelled compounds can be analysed using molecular and isotope based approaches and have proven to be a diagnostic tool for prediction of biodegradation to convince authorities on early close down without additional monitoring

• The detailed strategy with contingency milestones in monitoring was agreed by the regulator on basis of molecular biological tools to support traditional lines of evidence


5. Forensics 5.1. State of the art

• Different methods exist for forensic studies on contaminants. • Most common methods are fingerprinting, isotope analysis and evaluation of natural and

anthropogenic tracers (e.g. additives). • Can be used for finding sources of contamination (dating, localisation of spills), give insight in

conceptual site model and indications for natural attenuation. • Feasibility study and a careful assessment of accuracy and reliability of the results are

recommended.

5.2. Pharmaceuticals

• Pharmaceuticals are emerging contaminants and emerging to be used as tracer for forensics • Certain pharmaceutical tracers may be useful for forensic purposes in some cases • Careful evaluation of expenses versus results to be obtained is basis for selection of this tool. • Increased understanding of PPCP fate/transport remains key for usefulness.

5.3. Tree sampling

• Tree sampling can be used for screening of certain contaminants and aging a contamination • Tree sampling and analysis provides additional information to other characterization results. • Trees accumulate contamination in sap and in xylem (tree sap is the fluid transported in xylem

cells of a tree). • Phytoscreening focuses on the youngest tree rings (sap uptake of contaminants) and reflects

the current state of contamination in the root zone. • Phytoscreening can be used for mapping certain contaminants. • Dendrochemistry focuses on the annual rings of the tree (xylem) which reflect the changes of

the environment (contamination) in the root zone. • Dendrochemistry can be used for age dating of contamination (forensic, source identification). • Both tools request specialized use and evaluation. A few specialized laboratories are able to

execute the rather expensive analysis.


6. Overall conclusions and recommendations

6.1. General conclusions

The network meeting has shown a variety of possibilities to improve the conceptual model being the basis for all following actions and decisions (risk assessment, remediation, long term monitoring, baseline assessment....). Key conclusions from this meeting are:

• Many tools and for a good result are available: you have to think about and use different tools to have good insight in your conceptual site model.

• The key solution is the right combination and reasonable use of different tools. • All decisions for contaminated land management and remediation are made upon the data of

the site investigations: be aware of the importance of your data! • It is possible to decide upon uncertainties, but always pose yourself the question: is the level of

uncertainties the level you can manage?

6.2. Recommendations

Review with respect to changes in legislation

• Changes in legislation urge us to review current and new technologies for site characterization and monitoring.

No purge sampling

• In source zones the usual purged sampling can be a better method for remediation design. • For delineation of plumes both purged and no purge sampling methods give reliable results. • For risk assessment no purge sampling could be the preferred method. • More case studies are needed to prove of disapprove the above statements. • Based on the significance of the results and the consequences it is recommended to start trial

investigations under controlled conditions (large scale in lab).


Appendix 1. List of participants NICOLE Network Meeting on 24-27 May 2011, Copenhagen, Denmark Arakere, Suda LyondellBasell Industries USA Argyrou, Elli Adventus Europe Greece Bakker, Laurent Tauw BV NL Bastrup, John Ulrik GEO Denmark Bayersdorf, Hartwig Robert Bosch GmbH Germany Beddow, Helen Nuvia Ltd. UK Bell, Rob freelance journalist UK Bjerg, Poul Technical University of Denmark Denmark Blom, Marianne ENVIRON Corporation NL Boronat I Rodriguez, Jordi MediTerra Consultors Ambientals, S.L. Spain Burrows, Hazel BP International UK Buvé, Lucia UMICORE Belgium Camerani, Caterina AkzoNobel Sweden Constant, Sébastien SPAQuE Belgium Couto, Felipe Remedx UK Darmendrail, Dominique Common Forum France Davidsson, Lars WSP Environmental Sweden Dixon, Nik Grontmij Dixon Dörr, Helmut Dr. Dörr Consult GmbH Germany Dreiseitel, Martin F&R Worldwide, SRL Romania Drenth, Eize Oranjewoud NL Eisenmann, Heinrich Isodetect GmbH Germany Ejdeling, Göran Sweco Environment AB Sweden Euser, Marjan NICOLE Secretariat NL De Fraye, Johan CH2M Hill UK Garcia de la Rasilla, Mascha Eurofins Analytico NL Gevaerts, Wouter Arcadis Belgium NV Belgium Gous, Danie Dow South-Africa SA de Groof, Arthur Grontmij NL Groot, Hans Deltares NL Guibert, Pierre Environ France Hallgren, Pär Sweco Environment AB Sweden Hart, Catherine URS Nordic Sweden van Hattem, Willem Port of Rotterdam NL Heasman, Ian Taylor Wimpey UK Ltd UK Held, Thomas Arcadis Consult GmbH Germany Hertzmann, Daniel Sweco Environment AB Sweden van Houten, Martijn Witteveen+Bos NL Hübinette, Per Structor Miljö Göteborg AB Sweden Jacobsen, Frank Grontmij Denmark Jacquet, Roger Solvay S.A. Belgium Jubany, Irene Centre Tecnológic de Manresa Spain Kiilerich, Ole EPA Denmark Denmark Kirkebjerg, Kristian Grontmij Denmark Klaue, Bjorn Thermo Fisher Scientific Germany Kobberger, Gustav HPC Germany Kolle, Marcel Dura Vermeer Milieu NL Koomans, Ronald Medusa Explorations BV NL Koschitzky, Hans-Peter University Stuttgart Germany Langenhoff, Alette Deltares NL Lee, Alex WSP Environmental UK Liljemark, Anneli ÅF-Infrastructure AB Sweden Lucassen, Pim Philips Real Estate NL MacKay, Sarah WSP Environmental UK Madarász, Tamás University of Miskolc Hungary Maurer, Olivier CH2M Hill France France van de Meene, Chris SBNS NL


Menoud, Philippe DuPont de Nemours Switzerland Merly, Corinne BRGM France Mezger, Thomas Akzo Nobel NL Moll, Ulrich LyondellBasell Industries France Nguyen, Frédéric Université de Liège Belgium Nielsen, Pernille MediTerra Consultors Ambientals, S.L. Spain Van Nieuwenhove, Karel Antea Group Belgium van Noord, Wilfred AkzoNobel NL Ooteman, Kevin MWH NL Øster, Per A/S Dansk Shell Denmark Pals, Jan SBNS NL Pellegrini, Michele Saipem Italy Pentel, Robert GDF SUEZ France Plaisier, Wim ARCADIS NL van de Pol, Erwin Witteveen+Bos NL Polenka, Miloš GEOtest a.s. Czech Republic Polenková, Alena GEOtest Brno, a.s. Czech Republic Van de Putte, Wouter MAVA Belgium Raben, Henry Tauw NL Rajala, Päivi Närings-, trafik-, och miljöcentralen Finland van Riet, Paul Dow Benelux BV NL Schelwald-van der Kleij, Lida NICOLE ISG Secretariat NL Schmidtke, Joachim ENVIRON Germany GmbH Germany Schön, Carla AB Electrolux Sweden Schreurs, Jack Philips Environment & Safety NL Schrooten, Pieter ERM Belgium Sévêque, Jean-Louis UPDS France Shoesmith, Colin National Grid Property Ltd. UK Sinke, Anja BP International UK Slenders, Hans Arcadis NL Smeder, Maria Akzo Nobel AB Sweden Smith, Jonathan Shell Global Solutions UK Sørensen, Majbrith Grontmij Denmark Spence, Mike Shell Global Solutions (UK) UK Van Straaten, Mark MAVA Belgium Svensson, Håkan KemaktaKonsult AB Sweden Svensson, Janna Sweco Environment AB Sweden Thomas, Alan ERM UK UK Torin, Lena Golder Associates AB Sweden Törneman, Niklas Sweco Environment AB Sweden Touchant, Kaat Vito Belgium Travers, Mark Environ France Underwood, David Shell International Petroleum Company UK Undi, Tilly TOTAL RM UK Upton, Paul RSK Group Plc UK Vanderhallen, Joris Port of Antwerp Belgium Verhaagen, Paul Grontmij NL Visser-Westerweele, Elze-Lia NICOLE SPG Secretariat NL Voogd, Leon MWH NL van der Voort, Jack Ingenieursbureau Oranjewoud BV NL Waters, John ERM UK Williams, Stephen Thermo Fisher Scientific USA Wiltshire, Lucy Honeywell UK


Appendix 2 List of speakers NICOLE Network Meeting on 24-27 May 2011, Copenhagen, Denmark and provided links for more information on the subjects Strategies for characterisation Wouter Gevaerts, ARCADIS, Belgium <[email protected]>

Frédéric Nguyen – Université de Liège, Belgium <[email protected]>

Henry Raben, Tauw, the Netherlands <[email protected]>

Lena Torin, Golder, Sweden <[email protected]>

Field techniques Wouter Gevaerts, ARCADIS, Belgium <[email protected]>

Frank Lamé, Deltares, the Netherlands <[email protected]>

Majbrith Sorensen, Grontmij, Denmark <[email protected]>

Poul Bjerg, Technical University of Denmark <[email protected]>

Hans-Peter Koschitzky, VEGAS, University Stuttgart, Germany <[email protected]>

Isotope analysis and DNA-analysis Heinrich Eisenmann, Isodetect GmbH, Munich, Germany <[email protected]>

Alette Langenhoff, Deltares, the Netherlands <[email protected]>

Alex Lee, WSP, UK <[email protected]>

Forensics Helmut Dörr, Dr. Dörr Consult, Germany <[email protected]>

Joachim Schmidtke, Environ, Germany <[email protected]>

Gustav Kobberger, HPC, Germany <[email protected]>


Appendix 3. Collated abstracts provided by speakers NICOLE Network Meeting on 24-27 May 2011, Copenhagen, Denmark

State of the art on geophysics

Frédéric Nguyen, Université de Liège, Belgium

A key element in the remediation of contaminated sites is the ability to map and characterize the contamination distribution, and to assess the efficiency of in-situ remediation actions at the site scale. These tasks are more or less difficult depending on the degree of heterogeneity of the subsurface.

Geophysical mapping refers to the display of geophysical data and may provide qualitative information on contaminants, such as their location or extent. Geophysical mapping allows to reach a greater lateral coverage than drillings, with resolution ranging from a few centimeters up to several tens of meters, depending on the investigated depth. Generally, the resolution is inversely proportional to the investigated depth. Repeating a mapping in time may also provide information on the degradation of the contaminants if the degradation process affects the relevant physical property.

Geophysical imaging, on the other hand, may provide information on the location at depths of contaminants in the subsurface, on their concentration and eventually on their degradation. However, the retrieved information is indirect. It goes through two main filters before delivering the desired property. The first one is related to the transformation of the acquired geophysical data (e.g. traveltime or resistance) to the spatially distributed geophysical properties (e.g. seismic velocity or bulk resistivity), usually refer to as images. Geophysical images are numerical models obtained by the optimization of a certain number of criteria. The most important one being that the model is able to reproduce the measured data. These models, as for all numerical models, suffer from uncertainties and may also exhibit numerical artifacts. Fortunately, these drawbacks can be avoided by designing properly the geophysical survey, and quantified using image appraisal tools such as the resolution/sensitivity matrix or the depth of investigation index. The second filter links the recovered geophysical property (e.g. magnetic susceptibility) to the parameter of interest (e.g. metal content). These petrophysical relationships are generally obtained at the laboratory scale, where the studied medium is well controlled and understood. When applied in-situ, the validity of these relationships which depend on the physico-chemical of the environment and on scaling laws has to be verified in order to avoid erroneous interpretation.

This talk will give an overview of state-of-the art geophysical methods applied to contaminated sites in order to detect, map, characterize and monitor pollutants in the subsurface. We will review the relevance of geophysics depending on the target, and the limitations associated with the methods. Several relevant case studies will be presented and analyzed. We will also provide an overview of what to expect from geophysics in the future with a few research examples in the subfields of biogeophysics and hydrogeophysics.


Current trends for tracer techniques in environmental hydrogeology

Serge Brouyère, Université de Liège, Belgium

Tracer techniques have been applied for years for the characterization of contaminant transport processes in groundwater, in different context ranging from the delineation of protection zones around groundwater catchment areas to the quantification of groundwater fluxes and hydrodispersive processes in variably saturated underground media.

The objective of the talk is to present an overview on tracer techniques as applied to groundwater quality and pollution issues. A specific emphasis will be made on the applicability and potential of these techniques with respect to contaminated sites and on recent and ongoing technological developments of a single well tracer technique aiming at quantifying and monitoring groundwater and contaminant fluxes at such sites.

The presented concepts will be illustrated using field results and associated modelling exercise.


Direct push technologies: Overview, Applications and Limits

Carsten Leven-Pfister, University Tübingen, Germany, and

Hans-Peter Koschitzky, VEGAS, University Stuttgart, Germany

Dr. Carsten Leven, University of Tübingen, Center for Applied Geoscience Hydrogeology D-72076 Tübingen, Germany. [email protected]

Dr.-Ing. Hans-Peter Koschitzky, VEGAS, Research Facility for Subsurface Remediation, University of Stuttgart, D-70550 Stuttgart, Germany, [email protected]

Cost efficient and sustainable remediation, especially with innovative in situ remediation technologies, requires detailed knowledge of the subsurface in view of the pollutant distribution and the hydrogeology. So far commonly site investigations based on boreholes are used for the characterization of contaminated sites. In most cases these methods are time consuming, costly and as a consequence the site characterization is based only on a few drillings, i.e. investigations points, which results typically in insufficient information about the “real” extend and location of the contamination.

An alternative approach for site investigation is the use of Direct Push (DP) technology. This technology refers to a growing family of tools used to obtain subsurface investigations by pushing and / or hammering small-diameter hollow steel rods into the ground. By attaching specialized probes to the end of the steel rods, it is possible to conduct high resolution logging of rock parameters as well as to collect soil, soil gas, and ground water samples. Using DP technology it is feasible to get very quick and on site information about the three-dimensional pollutant situation. This information serves as a basis for decision about the ongoing stepwise site investigation. So overall more information can be received at lower costs. Besides the broad applicability of DP technology, it also allows for a target-oriented installation of monitoring equipment.

Due to the development of new powerful machines and tools, the application of DP technology increased strongly during the last years and became a viable alternative to conventional methods for site investigation. With the new generation of DP machines several sounding locations can be completed per day. Furthermore, under ideal conditions (e.g. soft, unconsolidated sediments) depths of more than 50 m can be reached.

The presentation will give an overview about the various direct push technologies and will also show the benefits of these techniques for investigation of contaminated sites exemplary from case studies.

DIETRICH, P. & LEVEN, C. (2006): Direct-Push Technologies. In: Kirsch, R. (Ed.): Groundwater Geophysics. Springer. 321-340

LEVEN, C. WEIß, H. KOSCHITZKY, H.-P. BLUM, PH. PTAK, TH. DIETRICH, P. (2010): Direct Push Verfahren, ISBN 978-3-510-39014-4, altlastenforum Baden-Württemberg e.V., Schriftenreihe, Heft 14

mailto:[email protected]�



Quantification of Mass Discharge from DNAPL sites in heterogeneous geological settings

Poul Bjerg, Technical University of Denmark

P. L. Bjerg ([email protected]), M. Troldborg, Ida Vedel Lange; Marta Santos; P. J. Binning (Department of Environmental Engineering, Technical University of Denmark, Kgs. Lyngby, Denmark)

DNAPL sources with chlorinated solvents are a major threat to groundwater. Contaminant discharge (mass/time) from contaminated sites is a useful metrics when evaluating the potential risk to downgradient receptors such as water supply wells and surface water bodies. A recent development is the coupling between contaminant source remediation and the plume response in order to assess the efficiency of site remediation and to optimize the resources spent to fulfill certain regulatory demands.

In the field, the mass discharge migrating from a contaminant source is typically determined across a control plane located downstream of the source and perpendicular to the mean groundwater flow. The uncertainty in a field-estimated mass discharge is highly related to the degree of heterogeneity of the mass flux distribution at this control plane. The more heterogeneous the mass flux distribution is, the finer the monitoring resolution network should be to ensure that the unmeasured areas in the control plane do not influence the estimate significantly. However, at most non-research field sites the number of monitoring wells is limited.

The degree of heterogeneity of the mass flux distribution at the control plane is caused by several factors, where spatially and temporally varying flow conditions and complex contaminant distribution in the source zone are considered most important. A quantification of the mass discharge and the associated uncertainty should therefore account for all these factors. However, it is not easy to describe and model the influence of such factors at a specific site, especially when data are sparse. Often the knowledge about e.g. the source and the geological and hydrogeological settings is limited, which makes it very difficult to conceptualize these elements and to incorporate them in a model. The previous studies of mass discharge uncertainty have not taken the influence of different conceptual site models into account.

We present here the results of a major effort on development and application of mass flux estimates in engineering and regulatory practice. The activities are related to two DNAPL contaminated sites in Denmark. Mass flux fences have been established at both sites and detailed descriptions of geology and hydrogeology exist. The monitoring of the mass flux fences was completed at site A in 2008 as a part of the risk assessment. At site B the temporal and spatial variability of mass flux estimates were evaluated during 2008 and 2009 by use of traditional wells (30 screens) and multi level samplers in the core of the plume (100 sampling points). The mass flux dataset for both sites are used to develop and test various methods for quantification of mass discharge and related uncertainties.

The presentation aims to give an overview of these activities and propose future challenges in the area.


Chlorinated solvent contamination, difficulties in understanding mass distribution, a case study

Pierre Guibert, Environ, France

Pierre GUIBERT, ENVIRON(1), www.environcorp.com

(1) ENVIRON France, Les Pléiades III - Bât. C - 320, avenue Archimède - 13857 Aix-en-

Provence cedex 3 – [email protected]

A past undetected leak from an underground solvent distribution tank system has lead to a significant subsoil contamination by trichloroethylene (TCE). Leak has been estimated at approximately several hundred tons of product over a 3-4 year period.

Following detection of leak, pump & treat wells as well as SVE were installed on source area to recover product and mitigate exposure to on-site workers. Since, numerous site investigations and risk assessments were engaged both on-site and off-site to better understand contamination distribution and evaluate potential risks to third parties and the environment.

These studies highlight that contamination is limited in the unsaturated zone, whilst important in the saturated zone and groundwater. TCE is observed as a dense non aqueous phase liquid (DNAPL) both on top as well as within a silt layer present on and off-site.

Chlorinated solvents have migrated as a dissolved phase with the general flow of the shallow aquifer but more specifically as both dissolved and DNAPL via a preferential pathway composed of backfilled historic river bed, before flowing into the surrounding rivers. The dissolved plume extends beneath a mixed industrial estate composed of mixed traditional, industrial activities and local municipal services.

This understanding of both the hydrogeological context and the distribution of the mass of DNAPLs was achieved after years of investigation programmes combined with the results of the remediation programme.

Based on environmental media sampling at exposure endpoints (soil-gas, ambient air, groundwater, surface water) risks to human health and the environment are below applicable acceptable risk levels.

DNAPL contamination within a complex hydrogeological context presents numerous challenges that will not permit full remediation thus making it difficult to prepare Remedial Action Plan (“Plan de Gestion de Site” - PGS), in accordance with French guidelines, which implies that source abatement must be achieved based on technical cost-benefit analysis.

This project has highlighted the following challenges/difficulties associated with the presence of TCE as DNAPL in a complex hydrogeological context: • Numerous investigation techniques (monitoring wells, soil borings, soil gas borings, membrane interface probe borings, seismic refraction, tracer tests) were used to identify and delineate DNAPL mass and understand the complexity of the natural context. All of these studies present limitations and uncertainties making the characterization of DNAPL source area or confirmation of the actual presence of free product difficult even when suspected. • With the presence of significant DNPAL in a complex hydrogeologic context partial recovery of free product appears as the only technically feasible solution as long as human health and environmental risks are controlled. • Non-extracted DNAPL will continue to generate a dissolved phase that will maintain the environmental impact at a long-term steady state. Long-term monitoring of various environmental media and the installation of deed restrictions will be the key components associated with long term risk management of the contamination.



Sampling of vapour

Majbrith L. Sørensen, Grontmij, Denmark

The presentation will give an overview of sampling techniques for assessment of vapour intrusion in houses and buildings. The presentation will give an idea about errors and other factors that influence your results and thus your sampling scheme should reflect the present geology and hydrogeology.

• Description of various sampling schemes, focused on intrusion of chlorinated and other volatile solvents.

• How are major and minor sources of error affect sampling and measurements. Absorbant media, passive sampling, humidity, air pressure, geology.

• How sampling can affect risk assesment. When to sample or wait? • Sampling with MIP, geoprobe and other field methods. Flux chamber and other quantitative

methods. • Description of typical case where sampling method can be essential for results • New upcoming sampling methods


Risk Assessment of Vapour Intrusion, focused on Chlorinated Solvents

Lena Torin, Golder, Sweden

Lena Torin, Golder Associates AB, Lilla Bommen 6, 411 04 Göteborg, Sweden

[email protected]

The issue of soil vapour intrusion from volatile contaminants in soil and groundwater into buildings, and especially chlorinated solvent chemicals, is becoming increasingly important in the world. In order to predict which sites might have a vapour intrusion problem, several countries have developed models and/or demand that soil gas and indoor air is sampled at the site. The different European countries do not have the same view and approach to this issue and it’s therefore difficult to present a view of how risk assessment of vapour intrusion is done in Europe. The presentation will therefore focus on current best practice and what should be avoided.

The presentation will give a short introduction on how risk assessment of vapour intrusion is done in general. The presentation will focus on vapour intrusion of chlorinated solvents as these chemicals make up most of the vapour intrusion problems. This is because chlorinated solvents can form large plumes within the groundwater, are persistent, have limited biodegradation in the vadose zone and are harmful to humans at very low concentrations.

The presentation will cover the following topics:

• Quality control of sampling data and the importance of developing a conceptual site model to understand variability and evaluate representative data for the risk assessment. What conditions pose a risk for underestimating the risk?

• When and how to use toxicological reference values, guidelines and occupational exposure standards. Trends and differences between countries. Since December 2010 the classification and labeling of certain substances within the EC are harmonized in the CLP/GHS-database.

• How does the use of the building affect the risk assessment? The different exposures for residential land use compared to commercial or industrial uses. What impact do building volume and ventilation rates have?

• Differences between some vapour intrusion models with regard to parameters and how validated they are against empirical sampling data. The largest collection of empirical data assembled is the USEPA vapour intrusion empirical database (http://iavi.rti.org).


Forensics - state of the art and possibilities in contaminated sites management

Helmut Dörr, Dr. Dörr Consult, Germany

Dr. Helmut Dörr

Dr. Helmut Dörr Consult, Germany – www.dr-helmut-doerr-consult.de

The general applicability, the investigation strategy and the benefits of forensic methods in contaminated site management are discussed. Results are presented from a case study (TPH-, BTEX and PAH-contamination in soil and groundwater) at an industrial site occupied by various tenants over several decades. The results are discussed with respect to the objectives of forensics of identifying the polluter(s).

The most common and approved forensic methods are the so-called fingerprinting, isotopic methods, the evaluation of multi-element distribution patterns and the investigation and interpretation of trace substances (e.g. additives) and environmental tracers.

Forensic methods are particularly suitable for the dating and localization of spills containing mineral oil and aromatic hydrocarbons. The source of contamination can also be investigated for selected heavy metals and CHCs. Other methods such as the determination of isotope ratios of pure substances and elements (Sr, Nd, Pb and U) can be used for the differentiation of pollutant sources, to determine the region of their origin. Nitrogen, boron and chlorine isotopes can be used to distinguish natural from anthropogenic sources. The analysis of tree cores allows a dating of spills (phytoscreening, dendrochemistry and dendrochronolgy) under certain conditions.

Forensic methods are not only suitable to identify polluters (location and date of spills) but can also add value in developing the site model for site specific risk assessment. Moreover, the identification and quantification of microbial decomposition potential can be a great benefit in the evaluation of cost efficient remediation strategies (MNA concepts).

The application of forensic methods and interpretation of forensic data are demonstrated by a case study. TPH-, BTEX- and PAH - fingerprinting together with data for MTBE and other specific chemical substances (MEK, Bitrex, Cyclohexan and Sulfur were suspected from a Phase I investigation) allowed the identification of locations and dates of spills of gasoline, heating oil/diesel, and heavy oil spills with differing accuracies of discrimination. Additionally, CFCH-, SF6- and tritium analyses were evaluated to describe the hydrogeological structure (contaminant transport behaviour, mean residence time, infiltration rates) of the contaminated aquifer for a risk assessment process.

http://www.dr-helmut-doerr-consult.de/�


Isotopes in contaminated sites management - principles and recommendations

Heinrich Eisenmann, Isodetect GmbH, Munich, Germany

The redevelopment of contaminated sites demands the application of efficient remediation technologies. Within this scope, the monitoring and enhancement of natural attenuation processes is a key strategy. However, clear evidence for biodegradation has to be provided. Isotope analysis delivers key information about contaminated sites. The isotope fingerprint of pollutants can allow discrimination of the initiators of groundwater contamination, while the enrichment of heavy isotopes by biological degradation can elucidate natural attenuation processes.

In situ biodegradation at contaminated sites can be assessed by the enrichment of heavy stable isotopes (13C, 2H) in the residual pollutants. In many cases, even the quantification of biodegradation is possible, because of correlation to isotope enrichment. The appropriate isotope enrichment factor has to be selected according to the compound of interest and prevailing redox conditions (see www.isodetect.de). As a consequence, isotope monitoring can provide detailed information on natural attenuation processes by a single sampling campaign. The percentual decrease of contaminants caused by micobiological activity downstream from the source as well as biodegradation rates can be derived. This enables also the discrimination of non-sustainable processes that further diminish contaminant concentration such as dilution or dispersion.

Numerous examples for successful isotope monitoring at sites contaminated with BTEX, MTBE or chlorinated ethenes have been described in scientific reports. As next, guidelines for this powerful exploring technique have been published by several environmental authorities. The presentation gives an overview about the state of the art in isotope monitoring of contaminated groundwater. In case studies, the quantification of biological attenuation of BTEX and chlorinated ethenes is demonstrated. For forensic purposes, the isotope fingerprint of pollutants can allow discrimination of the initiators of groundwater contamination. Finally, a variety of supplemental isotope surveys such as two-dimensional isotope monitoring (13C, 2H, 37Cl), isotope enrichment of electron acceptors (NO3 and SO4), and the exposition of isotope-labeled in situ microcosms (BACTRAPS) is shortly explained.

• Meckenstock, R., et al (2004) Stable isotope fractionation as a tool to monitor biodegradation in contami¬nated aquifers. J. Cont. Hydrol. 75: 215-255.

• US-EPA (2005) Monitored natural attenuation of MTBE as a risk management option at leaking underground storage tank sites. EPA/600/R-04/1/179. www.epa.gov/ada/download/reports/600R04179/600R04179-fm.pdf

• DECHEMA (2007) Held, T. et al.: Handlungsempfehlung: Mikrobiologische NA-Untersuchungsmethoden. www.natural-attenuation.de/media.php?mId=5623

• Fischer, A., Theuerkorn, K., Stelzer, N., Gehre, M., Thullner, M. Richnow, H.H. (2007) Applicability of Stable Isotope Fractionation Analysis for the Characterization of Benzene Biodegradation in a BTEX-con¬taminated Aquifer. Environmental Science & Technology 41: 3689-96.

• US-EPA (2008) A Guide for assessing biodegradation and source identification of organic ground water contaminants using compound specific isotope analysis (CSIA). EPA 600/R-08/148. www.epa.gov/ada/pubs/reports/600r08148/600R08148.html

• KORA (2008) Michels, J., Stuhrmann, J., Frey, C., Koschitzky, H.-P.: KORA Handlungsempfehlungen: Natürliche Schadstoffminderung bei der Sanierung von Altlasten. DECHEMA 2008. www.natural-attenuation.de/content.php?_document[ID]=6947&pageId=2647

• Eisenmann, H. Fischer A. (2010) Isotopenuntersuchungen in der Altlastenbewertung. Handbuch der Altlastensanierung 60:3511.


Closing down of remediation using Biotraps and DNA analysis – a case study

Alex Lee, WSP, UK

Advanced diagnostics and forensic techniques are broadening the scope of site investigations and expanding the lines of evidence available to soil and groundwater practitioners, problem owners and regulators. Some of the more popular and widely available techniques include the following:

Molecular Biological Tools – DNA / RNA analysis to characterise microbial populations and degradation processes. Can be used to provide clear lines of evidence to support theories of contaminant degradation via microbial processes;

Compound Specific Isotope Analysis – analytical processes that analyse the molecular weighting of contaminant species in order to assess degradation processes. These analytical methods can be used to provide evidence of contaminant degradation;

Groundwater tracers – tracers comprising DNA strands or physical dye tracers can be used to evaluate groundwater flow paths giving greater confidence and understanding of groundwater flow regimes

We present a review of the above techniques and a summary of different situations where they have been used in real life cases. Concluding from the case studies, we suggest where the techniques can be useful – what ‘operating windows’ or situations are appropriate.

We also use case studies to demonstrate the value to the problem owner and regulator that such techniques can bring in early close out of long term remediation schemes, saving time and money, but providing additional lines of evidence to allow regulatory close out.

Rather than being ‘out of reach techniques’ which are only available to the few and at high cost, we show how some of the more useful and accessible emerging methods are being used routinely to close out long term monitoring programmes.


Analytical challenges – It all starts with sampling

Frank P.J. Lamé

Deltares – The Netherlands

In testing the environmental quality of a site, the investigation follows a series of steps: planning of the sampling campaign, fieldwork including sampling, packaging of the sampled material, sample selection for analysis, pre-treatment of the sample, extraction or destruction of the sample, chemical analysis and reporting. Each of these steps can give cause to errors, while every error can contribute to a biased result and consequently might result in an incorrect conclusion about the environmental quality of that site. High costs might be involved for remedial actions while there still is a lot of uncertainty about the nature, extent and level of contamination.

Much emphasis is given to the analytical part of the characterization process: the reduction of the analytical error by means of e.g. calibration of the analytical equipment, blank samples, certified standards and round robin tests. Less attention is given to the origin of the analysed material, the sample, and the sampling strategy through which it was obtained.

A site investigation is based on assumptions about the environmental quality of that site, wherein the assumptions are based on information obtained on the history of the site, the processes on the site and the risks for these processes to have either contaminated the soil and / or the groundwater. A conceptual model of the site builds up in the mind of the consultant, and during the investigation process, this conceptual model should develop to such a level that it is sufficiently clear to come to decisions about the site. National, as well as international standards (e.g. ISO 10381-5) provide guidance for the sampling of contaminated sites.

As the sampling strategy is based on non-statistical information (the assumptions about the site), the accuracy of the overall process cannot be simply calculated. Indeed, the question arises if validation of the overall procedure is even possible.

Another issue is the characterization of a lot or stockpile of soil or soil-like material. What is the environmental quality of that material and can it be reused safely, or is treatment necessary prior to its reuse? Is it even possible to obtain a reliable estimate of the mean concentration of such a, potentially highly heterogeneous, lot? How many samples should be taken and what size (mass / volume) should the samples have? How can you ensure that the 2 grams analysed for heavy metal content are actually representative for a soil lot of, for example 2000 tons? In such cases assumptions about the past of the material are of less relevance, at least for the sampling strategy to be applied. A statistically based approach van be used which allows at the same time the quantification of errors made. For the sampling of soil stockpiles, a unique validated sampling strategy has been developed.


Pharmaceuticals in groundwater bodies as a forensic tool

Joachim Schmidtke, Environ, Germany

Over the past decade, pharmaceuticals and personal care product (PPCP) compounds have been identified and studied as emerging pollutants. Although many studies have been conducted regarding the presence of PPCPs in sanitary wastewater and the environment, these studies have been primarily focused on evaluating the extent, fate, and toxicological significance of PPCP discharges. For comingled environmental contamination in areas where multiple potential sources exist, PPCPs also have the potential to serve as forensic indicators of contaminant sources. Because public use of many PPCPs can be tracked to a specific date of drug regulatory approval or initial date of manufacture and trends exist for use of certain popular products, PPCP data can also be utilized in age dating analyses.

Ideal PPCP forensic indicators include persistent and mobile compounds that are in widespread usage in the population of interest. Wastewater sources that treat flow from multiple sources have an increased likelihood of the presence of a variety of indicator chemicals, although many compounds have also been identified in septic system discharges. Water quality studies conducted to identify the extent of the PPCP problem have detected a range of candidate compounds and have provided detection frequency data useful in selecting target compounds. Follow-on studies have provided additional data regarding of the persistence and fate of these compounds in surface and ground water environments, as well as survival in various wastewater treatment processes prior to discharge to the environment.


Tree sampling for Environmental Forensics

Jean-Christophe Balouet * & Gustav Kobberger **

Two methods are presented, both based on chemical analyses of wood samples from trees: 1. Phytoscreening Because trees uptake pollutants to which they are exposed, they can be used as indicators for pollutant releases in their vicinity. Soil and groundwater contaminants are uptaken and transported by sap in the outermost wood rings. These can easily be micro-sampled (0.2 g) and analyzed for the sap enriched contaminants. This method allows to qualitatively and quantitatively identify or exclude the presence of underground contaminants such as Chlorinated Hydrocarbons (PCE, TCE, DCE …). The correlation coefficient between tree and underground contamination is respectable (and up to 0.9). Whenever a site is properly vegetated, Phytoscreening can be used for a rapid identification or exclusion of contamination, for clarifying contaminant distribution by fast low cost measurements, for identification of release spots and delineation or monitoring of plumes. Being a standard method for CVOCs, BTEX and heavy metals (Cd, Cr, Cu, Hg, Ni, Pb, Zn) PIT currently investigates, if this method is also suitable for PAH, PCB and other organic compounds. 2. Dendrochemical Age-Dating Due to their seasonal growth annual tree-rings represent a bio-archive of the past. During this growth process elements taken up with the sap from the rhizosphere are being built in and fixed to wood cells. Accordingly and besides heavy metals pollutant specific tracer elements such as Chlorine (for chlorinated organic compounds like PCE) or Chlorine and Sulfur (for Fuel Hydrocarbons) are built in and fixed to the wood cells. This growth related element incorporation exclusively takes place within the youngest annual ring with the resulting element concentration depending on the respective element availability in soil and groundwater. The change in concentration over all annual rings of a tree core sample from the stem can be gained for 30 elements with the help of energy-dispersive X-Ray-analysis (ED-XRF). The ED-XRF is supported by a line scanner allowing an equidistant scan of a complete wood core from its youngest to its oldest ring at increments of 50 µm. This process delivers the concentration profiles of 30 elements over the total life time of a tree can be obtained at a very high temporal resolution. Accordingly, concentration anomalies of pollutant specific elements (tracers such as Chlorine) can be dated exactly to reveal the beginning and duration of an underground impact (such as by PCE). In order to rule out or confirm the possibility of alternative sources for the Chlorine anomalies (e.g. road salt), allied element concentration profiles (e.g. K, Ca, Mg, S) are compared for Cl-synchronous anomalies (multi-element-analyses). Other potential (environmental) influences are assessed by comparison with a sample taken from a control tree in the vicinity outside of the polluted area. By this means tree core samples can be used as „proxy-recorders“ documenting historic pollutant releases and impacts. If further historic data (e.g. documents) and information on soil and groundwater are considered, this method provides a reliable and very exact dating of the impact (by one 1 year) at the tree’s location. If more trees are available the spatiotemporal expansion of a plume as well as contaminant transport velocities can be revealed. This method is a powerful tool that provides an independent line of forensic evidence when attributing damages to polluters by exact age dating of impacts.

* Environment International, 2 ruelle du Hamet, 60129, France ([email protected]) ** HPC HARRESS PICKEL CONSULT AG, Kapellenstr. 45a, 65830 Kriftel, Germany ([email protected]




Isotopes and Microbes; a fruitful couple to prove natural attenuation of MtBE

Alette Langenhoff, Deltares, Netherlands

Alette Langenhoff, Jan Gerritse and Harry Veld

Deltares, P.O. Box 85467, 3508 AL Utrecht, the Netherlands, www.deltares.nl

Innovative monitoring tools are important for site characterisation, remediation studies or full site remediations. In complex situations, they can be crucial to understand the processes that occur at these sites, especially when routine monitoring (eg redox parameters, concentration of the contaminants) do not give sufficient insight in these processes. Furthermore, they can be applied at sites with insufficient progress in their bioremediation.

The following monitoring tools can be applied

1. Compound specific stable isotope (laboratory analyses on groundwater samples or pure product); 2. Bacteria and enzymes (DNA or RNA analyses on genes in soil- or groundwater samples); 3. Hydrogen (field analyses on groundwater samples). The presentation will explain the tools, and their efficient use with a focus to proof Natural Attenuation (NA) of methyl tert-butylether (MtBE). MtBE is an oxygenate added to fuel to improve combustion and reduce emissions of carbon monoxide and unburned hydrocarbons. The massive production and use of MtBE, combined with its high mobility and low intrinsic degradation rates make MtBE an important groundwater pollutant. We currently use the first two detection methods to provide quick and direct tools as indicators for NA of MtBE. Isotopes Biodegradation results in fractionation of carbon and hydrogen isotopes in the remaining MtBE. We used a relatively new “Stir Bar Sorptive Extraction” or “Twister” technique to determine stable carbon isotope ratios on low concentrations of MtBE and its metabolites, TBA and TBF (if present), and stable hydrogen isotopes of MtBE. On a contaminated site, stable carbon and hydrogen isotope analyses suggested aerobic degradation of MtBE.

Microbes We have designed quantitative real-time PCR assays to detect genes of key enzymes involved in biodegradation of MtBE, MtBE-monooxygenase or isobutyryl-CoA mutase, respectively (Fig 1). We detected different concentrations of these MtBE-degradation genes in cultures of MtBE-degrading bacteria and groundwater from contaminated sites.

CH3

H3C C O CH3

CH3

CH3

H3C C OH

CH3

O

OH

CH3

H3C C C

OH

methyl tert-butyl ether (MtBE)

tert-butyl alcohol(TBA)

2-hydroxyisobutyric acid (2-HIBA)

CO2 + H2O

+

Biomass(A) (B)

CH3

H3C C O CH3

CH3

CH3

H3C C O CH3

CH3

CH3

H3C C OH

CH3

CH3

H3C C OH

CH3

O

OH

CH3

H3C C C

OH

O

OH

CH3

H3C C C

OH

CH3

H3C C C

OH

methyl tert-butyl ether (MtBE)

tert-butyl alcohol(TBA)

2-hydroxyisobutyric acid (2-HIBA)

CO2 + H2O

+

Biomass(A) (B)

Figure 1 Degradation of MtBE, with the key enzymes for MtBE degradation: MtBE monooxygenase (A) and Isobutyryl-CoA mutase (B)

At contaminated sites, the presence of MtBE, TBA and isotopic fractionation correlated with the presence of MtBE-degradation genes. Statistical analyses showed a strong correlation between the concentration data, stable isotope analyses and the quantity of MtBE degradation genes.


Non destructive screening tools: overview, case study, relation with guidelines

Henry Raben, Tauw, the Netherlands

In soil and sediment studies, geophysical mapping is often used as a prerequisite to focus or guide traditional sampling and coring to the locations of interest. This way, synoptic and concise information on structure, composition and pollution of soils and sediments can be obtained.

Geophysical mapping or non-destructive site investigation gradually becomes more standard in site investigation for environmental impact assessments. Case studies show the benefits when searching for pollution in brown field sites, dumping locations, spreading of polluting aggregates in roads and the dispersion of pollutants in underwater sediments. Technologies as ground penetrating radar, gamma spectrometry, EM, XRF, mobile gas chromatography have been used for decades in the oil & gas industry and mining business but the application in soil investigation is relatively new. One of the reasons for this late application in environmental site investigation is the legislation that commonly prescribes how many drillings and samples should be taken at which locations. However, recent adaptations of this legislation for example in the Netherlands have created opportunities for the use of non-destructive site investigation in environmental assessment studies. Also the International en European standardisation organisations (ISO/CEN) are working on a general framework for the validation of screening technologies. Under this framework the XRF will be the first technology were an ISO standard will be published.

The presentation gives an overview of different technologies that are useful in soil and sediment assessment studies. The basic principle of the technology and the opportunities for application will be explained. The beneficial value of using non-destructive techniques is explained by a case study. Ground penetrating radar and XRF are used in the case study to preselect locations for traditional sampling methods. By using these techniques the drilling plan was optimized, the site was investigated in a shorter period of time which resulted in lower costs in contrary to the approach according to existing guidelines. The traditional sampling methods were mainly used to calibrate and verify the results of the non-destructive technique and to convince the public authorities.


Previous NICOLE Network Meetings State of the art of (Ecological) Risk Assessment, Stockholm, Sweden

16-17 June 2005

The impact of EU Directives on the Management of Contaminated Land, Cagliari, Sardinia, Italy

1-2 December 2005

Data Acquisition for a Good Conceptual Site Model, Carcassonne, France

10-11 May 2006

Making Managmenet of Contaminated Land an Obsolete Business – Challenges for the future (NICOLE 1996-2006 Ten Year Anniversary Workshop), Leuven, Belgium

5-6 October 2006

Redevelopment of sites – the industrial perspective. Akersloot, the Netherlands

14-15 June 2007

Using baselines in liability management: what do upcoming Directives require from us? Brussels, Belgium

15-16 November 2007

Sustainable Remediation, London, UK

3 March 2008

Environmental Decision Support Systems, Madrid, Spain

9-10 October 2008

Basics and Principles of Environmental Law, Brussels, Belgium

31 March 2009

Sustainable Remediation - A Solution to an Unsustainable Past? Leuven, Belgium

3-5 June 2009

From Site Closure to Disengagement, Douai, France

18-20 November 2009

Contaminated land management: opportunities, challenges and financial consequences of evolving legislation in Europe, Triest, Italy

5-7 July 2010

Emerging contaminants and solutions for large quantities of oil contaminated soil (Technical meeting), Brussels, Belgium

4 November 2010

For a complete overview of all networks meetings that have been held from the start of NICOLE up to now see www.nicole.org.


report of the nicole workshop - nicole network for ... · the nicole network meeting on 25-27 may...

Documents