report of the nicole workshop · • the grant of a budget for a project on inventory of european...

REPORT OF THE NICOLE Technical Meeting: Emerging contaminants and Solutions for large quantities of oil contaminated soil

4 November 2010

Brussels, Belgium

www.nicole.org

Compiled by Elze-Lia Visser, secretary NICOLE Service Providers Group

http://www.nicole.org/�

Report of the NICOLE Technical Meeting: Emerging contaminants and Solutions for large quantities of oil contaminated soil

Acknowledgements

NICOLE gratefully acknowledges

• UMICORE Brussels for hosting the event • The speakers and chairpersons for their contributions to the workshop and their comments on this

report • The members of the Organising Committee:

o Laurent Bakker (NICOLE-SPG / Tauw, the Netherlands) o Jean-Louis Sévêque (NICOLE-SPG/ UPDS, France) o Olivier Maurer (NICOLE-SPG/ CH2MHill, France)

• The NICOLE secretariats • Ian Ross (Arcadis, UK) and Jim Mueller (Adventus, Austria) for providing dedicated additional

information for members of NICOLE • Charles Pijls, Tauw bv , for providing the pictures for the front page of this report.

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. Emerging contaminants 52.1. Overview of the Environmental Fate of Perfluorinated Compounds 52.2. PFOS in the vicinity of two Swedish airports 62.3. In Situ Chemical Reduction (ISCR) Technology for Treatment of FREON in Groundwater 72.4. A State of the Art Discussion of the Charasteristics of 1,4-Dioxane and their Impacts on Remediation Approaches. 82.5. Conclusions 102.6. Recommendations and actions for NICOLE 11

3. Solutions for large quantities of oil contaminated soil 123.1. Large Scale Ex-Situ Bioremediation on an Operational Oil Field, Eastern Europe 123.2. Cost effective biological remediation of a large soil contamination at a gasoil terminal 133.3. Jet pump soil washing as a sustainable approach for cleaning large volumes of hydrocarbon impacted soils 153.4. Conclusions 163.5. Recommendations and actions for NICOLE 16

4. Overall conclusions 18

Appendix 1. List of participants NICOLE Technical Meeting on 4 November 2010 19


1. Background During the NICOLE network meeting in Madrid in October 2008 the Industry subgroup asked the Service providers subgroup to evaluate if and how the SPG can provide answers to rather persistent questions that live within ISG. These questions vary from remediation and monitoring techniques, knowledge on substances and general data for cost estimates of innovative techniques. Answers to these questions must not be seen as free consultancy but as a network activity. The SPG evaluated this request and concluded: • Answering the questions can have added value for the whole NICOLE community and has value in

sharing knowledge; • Tremendous opportunity, worthwhile organising the questions and answers and at the same time

input for the technical meeting SPG organises; • Better insight in the problems the Industry is facing

Based on the input from the ISG and SPG a project proposal was formulated and a funding budget was granted by NICOLE Steering Group.

The activities in the project aiming to answer the questions are: 1. specification of the questions 2. first step in answering via e-mail correspondence 3. second step in answering via technical network meeting 4. third step in answering via a funded project by NICOLE and/or other partners The first activities of the project have been carried out and resulted in: • the organisation of the Brussels Technical Meeting of 4 November 2010 on 2 technical questions • the grant of a budget for a project on inventory of European practices and experiences permitting

landfills and mobile treatment plants for contaminated soil’ – Criteria limits between hazardous and non-hazardous landfill material – Authorizing mobile treatment plants

This project is planned for 2011.

The technical meeting on 4 November 2010 was dedicated to mobilize knowledge and experiences to provide input or direct answers on two questions: 1. What do we know and what don’t we know about special contaminants such as

Perfluorooctanesulfonic acid (PFOS), Chlorofluorocarbons (CFCs) and Dioxane? 2. What (sustainable) treatments can be used to clean large quantities of petroleum hydrocarbons

impacted soil? This report reflects the Technical meeting and the outcome of discussions. This document doesn't necessarily reflect the opinion of NICOLE and/or all individual NICOLE members or member organisations.


2. Emerging contaminants 2.1. Overview of the Environmental Fate of Perfluorinated Compounds

Jason M. Conder, ENVIRON USA (Richard J. Wenning, Mark Travers, Marianne Blom, ENVIRON)

Introduction Perfluorinated compounds (PFCs), such as perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA), are emerging chemicals of concern in aquatic and terrestrial systems. The physicochemical properties of PFCs and their precursor compounds are such that chemical fate is not well described or predicted by the environmental fate models typically used to evaluate other organic compounds of concern. Further, there is insufficient understanding of environmental levels (e.g., groundwater, soil and sediment), bioavailability, and the hazards posed to humans and wildlife to support decision-making about remediation when these chemicals are found in waterways and on industrial properties.

Uses and sources PFCs are used for its repellency and surfactant properties e.g. in metal plating (non stick cookware), firefighting foams, textiles and other industrial applications. Aside from contaminated sites from production of PFASs, fire fighting (training-) locations, waste water treatment plants and landfills are important sources. Persistence A key aspect of PFCs is high environmental persistence, especially the perfluorinated carboxylates (e.g., PFOA) and sulfonates (e.g., PFOS). Water solubility and partitioning to solid phase; bioaccumulation Water solubilities of PFCs are relatively high, yet partitioning to solid phases can occur, and has led to the accumulation of perfluorinated carboxylates and sulfonates in soil and sediment and bioaccumulation in fish and wildlife. Partitioning is directly related to the length of the fluorocarbon chain and functional group, with sulfonates (e.g., PFOS) expressing higher partitioning behaviour than carboxylates (PFOA). Due to the weak acid nature of PFC sulfonates and carboxylates, pH can affect partitioning, with stronger partitioning observed for the protonated acid form at lower solution pH. Not volatile The stable sulfonates and carboxylates such as PFOA and PFOS are not volatile. Remediation Remediation of groundwater, soil, and sediment to address human health and ecological risks will likely focus on manipulating aqueous partitioning of impacted media. Initial applications involving traditional sorbents such as activated carbon had limited success due to the high water solubility and low partitioning behaviour of many PFCs, especially carboxylates with short fluorocarbon chains such as PFOA. Other remedial applications, such as chemical oxidation, have shown promise in laboratory trials, but the feasibility has yet to be demonstrated on a field-scale remediation in the same manner as activated carbon treatment.


Precursor compounds and unknown transformation processes Additionally, there are a host of poorly-characterized precursor compounds that are able to transform to the stable perfluorinated carboxylates and sulfonates under a variety of environmental conditions. Mechanisms of the transformation processes remain unknown, and many of the precursor compounds exhibit properties (e.g., high volatility) that are very different than the carboxylate or sulfonate end products. Understanding of environmental behaviour: more work needed It is evident that more work is needed to understand the environmental behaviour of PFCs and to develop effective approaches to management of these compounds in waterways and at industrial properties. More information available on www.nicole.org • Presentation Jason Conder NICOLE Technical Meeting 4 November 2010 Brussels • Jason M. Conder, Roberta Hoke, Watze de Wolf, Mark H. Russel and Robert C. Buck, Are PFCAs

Bioaccumulative? Environ. Sci. Technol. 2008 Vol 42, No 4 • [email protected].

2.2. PFOS in the vicinity of two Swedish airports

Karin Norström, IVL Swedish Environmental Research Institute (Tomas Viktor, Jörgen Magnér)

Introduction AFFF (A triple F, Aqueous Forming Film Foam) is a fire fighting foam traditionally used at big airports where the extinction of petroleum-based fires needs to be given the utmost priority. AFFF contains PFOS. It has been used at Arlanda and Landvetter airports at the frequent fire exercise at specifically designed exercise platforms. Despite that, large quantities have leached out in the vicinity. Site investigation The occurrence, distribution and risks for humans and the ecosystem regarding PFOS have been investigated. Samples (surface water, sediment, and fish) from lakes and catchment areas surrounding the two airports have been extensively sampled and analysed. Possible measures are being examined to minimize further dispersion of PFOS. Results of site investigation At both Arlanda and Landvetter, the results show a clear correlation between the levels of PFOS in surface water and the distance from the sampling location to the area where AFFF has been used at exercises. In the lake Halmsjön, directly bordering Arlanda airport the level of PFOS was 140 ng/l. This is at least 50 times higher than in surface water from the background areas. In sediment from the same lake, the level of PFOS was 20 ng/g d.w. In Perch (fish) muscle tissue the levels of PFOS were 300-1000 ng/g f.w. Calculations conclude that 1 portion of the fish per month from the most contaminated lake is above the acceptable level for human uptake.

Questions The detected levels have raised many questions, i.e. are the levels a problem for the local ecosystem? How to accomplish a risk assessment for humans living in the area? How long will it take before the levels reach background concentrations?

mailto:[email protected]�


Precautionary measures Based on recommendations from the project fishing (and the consumption of fish) in on of the two lakes has been prohibited by local authorities. Today, at Arlanda and Landvetter airport activated carbon is being used to clean contaminated groundwater from PFOS. Finally, fire fighting foams containing PFOS that were on the market before 27 December 2006 are banned from use after 27 June 2011. More information available on www.nicole.org • Presentation of Karin Norström at NICOLE Technical Meeting 4 November 2010 Brussels • [email protected] 2.3. In Situ Chemical Reduction (ISCR) Technology for Treatment of FREON in Groundwater

Jim Mueller, Adventus (Mike Mueller, Elli Argyou)

Introduction In situ chemical reduction (ISCRTM) as defined herein, describes the combined effect of

• stimulated biological oxygen consumption (via fermentation of an organic carbon source), • direct chemical reduction with zero-valent iron (ZVI) or other reduced metals, • and the corresponding enhanced thermodynamic decomposition reactions that are realized at

the lowered redox (Eh) conditions. EHCTM, a compound used for this technology is a solid or liquid material that provides:

• Controlled-release, hydrophilic carbon source; • Micro-scale (5- 50 um) zero valent iron (ZVI) or other reduced metals (Zn, Al), at 5 to >40%

weight; • Major, minor and micronutrients.

A number of enhanced reductive dehalogenation (ERD) and other accelerated anaerobic bioremediation technologies exist (e.g., emulsified oils, oils, carbon-based hydrogen release compounds) that offer similar responses. However, the original ISCR substrates are able to provide ZVI thereby yielding Eh values as low as -600 mV under field conditions.

Pilot scale testing on Freon The use of EHC® ISCR technology for treatment of FREON and myriad chlorinated solvents has been documented. For example, the constituents of interest (COI) at a Site in USA were tetrachloroethene (70 µg/L), trichloroethene (500 µg/L), cis-1,2-dichloroethene (1,900 µg/L), 1,1-dichloroethene (115 µg/L); 1,1,1-trichloroethane (130 µg/L), and 1,1-dichloroethane (600 µg/L). Various FREON compounds were also present. A set of four flow-through column systems was set up, which included a control column and three EHC columns, established to document the ability of EHC ISCR technology to treat the site COIs. After 84 days of treatment, the EHC systems also showed good removal (>99%) of all COI: all FREON compounds were rapidly removed under all EHC treatment conditions. Treatment options for CFC’s The environmental fate of CFC’s (chlorofluorocarbons (Freon, Flugene, Frigen) is highly dependent on mass weight and as such the more halogenated (such as PFOS (perfluorosulfonated compounds) and PFOA (perfluorooactanoic acids)) are more persistent than lesser halogenated CFCs. The same effect is observed on treatment options based on:

• Volatilization • Aerobic co-metabolism (methane, propane, NH4) • Anaerobic biotransformation • Abiotic reductive dehalogenation

Schematically the characteristics are shown in the figure, drawn from Hohener et al., Critical Reviews in Environmental Science & Technology, 33(1):1–29(2003).



Challenges with CFCs: Characterization and Treatment • CFCs are essentially omnipresent • Analytical standards not readily available • Haloalkane remedial applications are limited to:

o Anaerobic biotransformation – ISCR Pilot (laboratory and above ground field scale, presented) o Abiotic reductive dehalogenation – ZVI PRBs (field scale, presented) o Chemical oxidation (activated persulfate) – not presented

More information available on www.nicole.org • Presentation of Jim Mueller at NICOLE Technical Workshop 4 November 2010 Brussels; • Hohener et al., Critical Reviews in Environmental Science & Technology, 33(1):1–29(2003); • Several other articles; • [email protected] 2.4. A State of the Art Discussion of the Charasteristics of 1,4-Dioxane and their Impacts on Remediation Approaches

Bart Vanhove, CH2MHill (Tom Simpkin, Jason Cole)

Introduction There are a number of compounds that were used as additives to primary industrial chemicals. For example, a number of stabilizers were added to solvents to improve their performance and life duration. When the primary industrial chemicals were accidently spilled or released into the environment, they were often the primary focus of the remediation efforts, with little attention paid to the additives. In some cases, after a number of years of operations of the remediation system, it was observed that the additives were present in relatively small quantities, but still important enough to create significant subsurface contamination issues. Their physical and chemical properties often made them more mobile and recalcitrant than the primary industrial chemical for which the remediation system was designed. 1,4 Dioxane is an example of one such solvent stabilizer that has been recently identified as a contaminant of concern at a number of sites. Physical and Chemical characteristics of 1,4 Dioxane 1,4 Dioxane is volatile in its pure form. Dissolved in water 1,4-Dioxane exhibits very little tendency to partition to the gas phase. It has a small Henry’s coefficient (3E-03 Atm.L.mol-1) and is quasi infinitely soluble in water. Retardation equals 1 and as such it moves with the velocity of the groundwater; there is no chemical interaction with the aquifer matrix.



1,4 Dioxane exhibits recalcitrant behaviour: physically and chemically stable, no significant degradation in subsurface environments is known. Aerobic degradation is observed at laboratory and pilot scale (cometabolic and direct with dioxane as energy source).

Usages and Sources 1,4 Dioxane usages • Solvent Stabilizer1

• Surfactants;

(as acid scavenger or metal Inhibitor). Formulation data review from 1,1,1,-TCA manufacturers indicate 1,4-dioxane addition from 0% to 4%;

• Aerosol Additive; • Polyester by-product. As it is typically used as an additive to other chemicals, it is therefore not likely to be present as a free phase product (in contrast to 1,1,1 TCA); the total mass present in the subsurface is smaller compared to chlorinated solvents. Its high solubility, low retardation, and low natural degradation usually results in large plumes if groundwater velocities are high.

Site Investigation Because of its specific characteristics there are concerns with its detection in soil and groundwater. Environmental laboratories are still establishing Protocols for Reliable Quantification. GC-MS seems to be the best method; sample preparation brings difficulties due to the low Henry’s constant and the high solubility. Typical detection limits are 30 – 100 µg.l-1, above some target levels. Risk Assessment 1,4 Dioxane is possibly carcinogenic. Given its characteristics it will relatively not affect soil or sediment. Impact to the surface water is reduced due to photo destruction. 1,4 Dioxane will be primarily a groundwater problem since it is more mobile and moves faster and further than the solvents. Actual risks can be found at drinking water extractions, potential risks can be off-site groundwater quality. Remediation Strategies Due to its chemical characteristics only a few of the more common in-situ treatment approaches may be applicable to 1,4 dioxane and there is little full-scale experience with in-situ treatment: • Air Sparging (stripping\volatilization): not effective; • Adsorption: not effective; • Phytoremediation: limited field data (1 field demonstration in U.S.), laboratory and greenhouse

results demonstrate treatment using hybrid poplars is feasible. Plume depth and growing seasons control application;

• Biodegradation: aerobic degradation is feasible and documented. Technology has not been deployed at field scale for in-situ dioxane treatment;

• In-Situ Chemical Oxidation: best body of evidence for in-situ Dioxane removal. Pump and treat approaches are potentially effective, because of the high mobility of 1,4 dioxane. Full-scale ex-situ treatment is well documented. Ex-situ groundwater treatment is challenging because of 1,4 dioxane’s high solubility. Advanced oxidation processes have been proven to be effective, although there may be a number of site specific challenges. Biological treatment has also been used in a limited number of cases, but it is only effective in an aerobic, co-metabolic system. Such systems are challenging to effectively operate.

More information available on www.nicole.org • Presentation of Bart van Hove NICOLE Technical Meeting 4 November 2010 Brussels • [email protected]

1 Main focus of the presentation



2.5. Conclusions

Emerging contaminants It was evaluated that it is valuable to members to learn about the properties of emerging contaminants. Since only a few of these have been dealt with in this meeting, a meeting on other emerging contaminants could be organised by NICOLE.

Knowledge on emerging contaminants The contaminants dealt with in the Technical meeting have all a different kind of behaviour compared to the “classical” contaminants. Its persistence, often toxic influences in combination with a high solubility in the groundwater and low retardation makes it a contaminant of concern for sustainable land use. The research in this field is just starting and not many data are available yet. This calls for • A need to have these scarce data available and for a need of ongoing research on e.g. toxicity,

methods for analysing, (in-situ) treatment options and more. Only pump and treat with GAC purification systems have been proven effective, but have a low cost-effectiveness;

• Development of a very good Conceptual site model to evaluate impacts based on current knowledge to deal with on a risk based approach.

Single site issue vs. global issue The focus of NICOLE is on contamination on single sites. For example contamination on fire fighting places if fire extinguisher with PFOS additives has been used. To be prepared it is valuable to share information in the NICOLE network. Especially information on the behaviour of the contaminant, toxicity data, possible treatment options and practical experiences is needed for this. Global issues on diffuse contamination and background values are not the focus of NICOLE.

Methodology, ways to deal with emerging contaminants Since the publication of the Stockholm Convention list (2001) with an initial number of 12 persistent organic compounds 9 emerging contaminants were added. Every year a contaminant is added to the list. To be able to deal with these emerging contaminants in a pragmatic way, experiences could be shared in the NICOLE network. This might lead to a document (e.g. checklist) aiding industry and service providers on the approach and management of these emerging contaminants. This document should have a technical focus from a responsibility point of view.

Inventory of regulations Not much attention has been paid in the technical meeting to the regulatory aspects of these emerging contaminants in the soil and groundwater. It is not clear whether and how different member states act upon this. It might be worthwhile to make an inventory on how EU and member states act upon emerging contaminants.

Evaluation of behaviour Each newly developed molecule has new characteristics and new behaviour. Time is needed to test and evaluate the behaviour before launching new molecules into society and the environment. Since behaviour may highly differ from existing contaminants this might call for different approaches to evaluate these compounds. This should not only be mono testing but also testing of synergetic behaviour. It is not clear whether REACH can deal with these aspects in a proper way.

Attention to metabolites Not only is the (toxic) behaviour of the “source” contaminant important. It is equally important to pay attention to the metabolites that are formed in the chain of reactions that can take place in the soil, surface water and groundwater. Even remedial actions may induce the forming or release of more persistent contaminants.

Analysis of persistent contaminants Based on scarce data on relatively high toxicity of some of the compounds, a need for very low detection levels occurs. Current methods are not yet able to reach these low detection limits. For risk based land management the need is felt to develop methods to detect low concentrations.


2.6. Recommendations and actions for NICOLE

1. Two Make data and information (e.g. links to literature) on the emerging contaminants coming from this technical meeting available for members via www.nicole.org;

2. Compose a document (e.g. checklist) on practical ways to deal with emerging contaminants; 3. Organise an event on other emerging contaminants from the Stockholm list if relevant for NICOLE

members; 4. Make an inventory of existing regulations on emerging contaminants; 5. Make clear to research community and funders that there is a need for further information and

research on the behaviour of the contaminants this technical meeting dealt with. The organising committee of the Technical Meeting will make a proposal for the NICOLE Steering Group to work on these recommendations. Any input from NICOLE members for this proposal is appreciated.



3. Solutions for large quantities of oil contaminated soil 3.1. Large Scale Ex-Situ Bioremediation on an Operational Oil Field, Eastern Europe

Richard Clayton (WSP, UK)

Introduction Bioremediation can provide an environmentally sound and cost-effective method of treating large quantities of mineral oil contaminated soils, typically associated with the production and refinery processes of the oil and gas industries. Bioremediation is generally defined as an accelerated process using micro-organisms (indigenous or introduced) and other manipulations to degrade and detoxify organic substances to harmless compounds, such as carbon dioxide and waters, in a confined and controlled environment. When properly managed, it can: • Enable the appropriate re-use of treated soil; • Minimise disposal of waste soil to landfill; • Provide adequate protection of human health and the environment.

It is not a new concept and is being increasingly used as a relatively economical environmental remediation technology. Ex-situ treatment of soil is generally undertaken in contained and managed biopiles, windrows or, subject to limitations, by landfarming. Bioremediation activities typically require large areas of land and prolonged treatment durations.

Assessment Traditionally, before starting a bioremediation project, a thorough assessment of site conditions should be made together with an appraisal of feasible treatment options. This requires high density subsurface information, along with an appropriate assessment of risks which is aligned to local legislation. Example case: crude oil site in Eastern Europe Increasingly, it is found that the remediation of large scale oil contaminated soils is being required in more difficult to access locations, and in much less developed legislative regimes. Whilst there may be no immediate driver to undertake a clean up, there is a low probability high consequence risk of having to undertake remediation, driven by changes in local legislation, or by corporate responsibility goals. In this case there is little data, and little legislative framework to assess the feasibility, scale and costs of such a clean up. The aim of the work is to assess the feasibility and economic implications of a very large scale (>150 hectares) oil contaminated soil clean up. The site has a long history of crude oil related activity, which has resulted in a significant legacy of contamination issues. As a part of this assessment a soil treatability trial at a large site is being prepared. There is very little site data or information, and in no legislative regime by which to assess whether such clean up is required, or to what level. Therefore, the general aim of the work is to identify appropriate technologies that can be utilised on a large scale, with the long term objective of providing demonstrably cleaner areas, both through visual improvement and through the reduction and removal of contaminated areas. Field trials In this case, rather than proposing detailed investigations and risk assessments, an initial phase of treatability trials for a number of the most common ex-situ bioremediation techniques have been decided (windrows, biopiles, landfarms) using various levels of enhancement (nutrient addition and bioaugmentation). The aim of the initial trials is to apply bioremediation techniques to the impacted soils on-site, in order to determine the feasibility of the technology and its long term suitability. The performance of the various trials will be monitored and measured during a six month period using a combination of field based and laboratory methods and techniques to gather a robust evidence base. The field trials will treat 2000 m3 contaminated soil. Centrifuge and Thermal trials will be progressing at the same time executed by other parties.


The contaminated media will include impacted soils, neat oils and sludges and a key step in designing the trial will be the management of waste streams at the source (the impacted area) to create suitable treatment (waste) streams of differing contaminant profiles and moisture content and trial the effectiveness of different treatment techniques.

Preliminary results The initial challenges that have been faced during the project thus far have included: • A lack of site data regarding the physical, biological and chemical composition of the soils; • A lack of site wide monitoring data for air quality and other potentially hazardous conditions, that

operatives may be exposed to; • The impacted soils appear to be predominantly sandy clays and the oil contamination extends

through to the heavy end range with high levels of asphaltenes/waxes etc; • The availability of plant, equipment and materials is fairly limited and adaptability throughout the

project will be key. Most of the technical and specialist equipment is being sourced and commissioned within the UK and then transported to site. General plant and readily available material, such as organic amendments and nutrient fertilisers are being sourced locally to minimise the transport requirements, engaging local suppliers and communities to provide a more sustainable approach. Ultimately the aim is to train and up-skill the local resource, thereby enhancing in country development with ongoing technical support;

• A lack of laboratory facilities in-country, will result in the need to send a lot of samples out of country for analysis, although much field data will be gathered to measure performance and inform process decisions;

• A lack of transparent environmental framework or regulatory guidance will provide uncertainty as to the acceptability of proposed works and remediation standards, however the aim is to undertake works to recognised standards and industry best practice.

More information available on www.nicole.org • Presentation of Richard Clayton for NICOLE Technical Meeting 4 November 2010 Brussels • [email protected]

3.2. Cost effective biological remediation of a large soil contamination at a gasoil terminal

Charles Pijls (Tauw, Netherlands)

Introduction to the case In the Rotterdam Harbour a seasonal gasoil storage terminal with four 90.000 m3 tanks of 90 m diameter was decommissioned in 19xx. A soil investigation revealed the presence of a free phase floating layer of 23.000 m2. Furthermore about 150.000 m3 gasoil contaminated soil was present. The extent of the groundwater contamination was limited. The contamination was caused by a leaking valve and was not discovered for many years. The property was leased form the Port of Rotterdam and had to be returned in its original state, without contamination. The Port of Rotterdam was planning to redevelop the site for container storage. Several alternatives were assessed for remediation of the soil (in situ treatment, excavation and immobilisation or on site thermal or soil washing). Finally it was decided to excavate the soil and treat it in situ/onsite.

First phase remediation: isolation, removal free phase, biopile trials As a first step the site was hydraulically isolated with an injected bentonite slurry wall to minimise groundwater inflow. Prior to excavation the free phase gasoil was removed with a system of drainage ditches. Removal of about 1.200 ton free phase gasoil took 8 months. Hindrance of smell was a factor of concern and has been taken into account during the free phase removal. The contaminated soil was excavated and prepared for treatment in in situ biopiles. Soil preparation consisted of crushing and mixing with nutrients. The soil was treated in situ in constructed biopiles, which were optimally prepared for aerobic biodegradation. The soil treatment was tested in a constructed biopile. The heat produced



by the biological oxidation was sufficient to increase the temperature in the biopile up to more than 50° C. Despite these high temperatures the biodegradation process was not interrupted. Second phase: full scale treatment After a successful pilot treatment the full scale treatment of 150.000 m3 soil was finalised in 18 months. The project was finalised with a closed soil balance. It was not necessary to dispose of contaminated soil off site or to transport clean soil to the site. The treated soil layer was covered with a layer of 1 meter clean soil that was separated during the excavation of the contaminated soil. After the soil treatment the site was handed over to the Port of Rotterdam. The site was redeveloped soon after.

Construction of biopile

Results in short • Average residual TPH level in soil 660 mg/kg • Full scale treatment within time frame of 18 months • Closed soil balance • 5 year groundwater monitoring indicates :

o Average TPH level remains < 100 µg/l o Maximum TPH level observed 350 µg/l

• No BTEX observed • Treatment cost: 25 EUR/m3 • Total project cost: 45 EUR/m3 Conclusions and lessons learned The biological soil treatment process is a highly sustainable remediation, with a small carbon footprint compared to other alternatives, with minimal waste production and a high removal efficiency. In similar cases the preferred remediation approach would be the same. Lessons learned • Resistivity measurements can be applied to localize free phase LNAPL • Ground Penetrating Radar can not detect LNAPL • On site biological treatment is cost effective and sustainable • Biological treatment can eliminate migration risks • Biological treatment can be performed in a limited time span • High temperature (> 40° C) does not inhibit biodegradation


More information available on www.nicole.org • Presentation Charles Pijls NICOLE Technical Meeting 4 November 2010 Brussels • [email protected] • SKB Cahier Oil in the soil, (SKB Cahiers are handbooks that contain summarised and concise

descriptions of important subjects relating to soil). This cahier has been uploaded to the www.nicole.org website and can also be downloaded from http://www.nsp-soil.nl/pagina.asp?id=1138&L=2

3.3. Jet pump soil washing as a sustainable approach for cleaning large volumes of hydrocarbon impacted soils

Ian Ross (Arcadis, UK), Mike Turland (Vinci, UK)

Introduction Jet pump soil washing is a remediation technique that separates and cleans contaminated soils. It can be used to remove a variety of organic and inorganic contaminants such as hydrocarbons, metals and pesticides from soils. It can significantly reduce the volume of contaminated soil requiring disposal and can be coupled to other remedial techniques such as ex situ bioremediation or ex situ chemical oxidation to potentially eliminate the requirement to dispose of soils to landfill. The technology can be applied at specific site at mobile treatment hubs or at centralized treatment centres. Principles of soil washing Soil washing is a separation process where smaller soil particles which generally host the majority of the contamination are separated from the bulk soil fractions and (or) contaminants are removed from the soil into process water (possibly assisted using surfactants). The fines fraction (‘filtercake’) may go to landfill or potentially can be further treated by chemical oxidation or biopiling on site. By removing the majority of the contamination from the soil, the bulk fraction that remains can be recycled/reused as backfill on site or disposed of relatively cheaply as non-hazardous material. Process of jet pump soil washing The process uses an initial volume of water which is cleaned and recycled around the plant, minimizing the requirement for resources. The energy requirements of the plant are minimal in comparison to thermal technologies, moisture content assists with washing and the plant throughput can exceed 40 tons per hour. The technology can be deployed to treat large volumes of hydrocarbon impacted soils and complex mixtures of anthropogenic waste containing hydrocarbons, chlorinated solvents and pesticides. Major advance is the use of jet pumps which use high pressure water jets to remove adherent contaminant films from coarser particles via a process known as attrition scrubbing.

Jet-pump hopper for scrubbing soil particles



http://www.nsp-soil.nl/pagina.asp?id=1138&L=2�

http://www.nsp-soil.nl/pagina.asp?id=1138&L=2�


Results As soils are cleaned and separated into various particle sizes they are suitable for reuse on site as an engineered product, there is also usually a significant saving in the requirement to import materials to replace the normally landfilled material. Soil washing is suitable for use in sensitive developed areas (such as residential areas) and can often reduce the overall impact associated with remediation of a site (such as noise and dust issues). Typical Jet Pump Soil Washing Costs • Treatability Studies £5,000 - £40,000 depending on the complexity and requirements for process

water and filtercake treatment. • Small Scale Pilot Trials £1,000 - £3,000 • Full Scale Pilot Trials £10,000 - £20,000 • Typical setup costs - transport, commissioning, infrastructure, plant (hire/purchase), £30,000 -

£40,000 • Operating costs – electricity, labour, maintenance circa £20 - £25 per tonne depending on plant

configuration and through put. Capital costs of the machine are addition to this and depend of the depreciation period.

• Quality Control Sampling – costs highly variable depending on chemical analysis and validation frequency required.

• Decommissioning. £25000 • Process Water treatment – fines removal costs included within general operation, additional costs

for specialist water treatment e.g. ion exchange More information available on www.nicole.org • Presentation Ian Ross and Mike Turland NICOLE Technical Meeting 4 November 2010 Brussels • [email protected] • [email protected] 3.4. Conclusions

A lot is known It is generally concluded that a lot of experience and information exists on the treatment of oil contaminated sites. With today’s knowledge we can develop plans and execute them to remediate in cost effective ways. It is necessary to disseminate the wealthy existing knowledge in a proper, dedicated way for those dealing with (large quantities) oil contaminated soil. NICOLE could play a role in this e.g. to define the need and/or set up a kind of database (“Nikipedia”).

HSE issues during operation For a sustainable solution the HSE issues for the operational personnel during the remediation should be taken into account in case of remediation during a long period. Also hindrance for the public during remediation should be taken into account.

Reuse of energy from contamination In the discussions on sustainability of remedial options this issue is worthwhile to explore.

Matrix or decision tree There is little need to develop another matrix or decision tree on remedial options for large quantities of oil contaminated soil. 3.5. Recommendations and actions for NICOLE 1. Several Make information from this meeting available to NICOLE members; 2. Explore the opportunities for a database on relevant knowledge and experiences (maybe a

“Nikipedia”);




3. Explore reuse of energy as a sustainability aspect in the NICOLE Working Group Sustainable remediation;

4. Explore HSE issues during operation of remediation as a sustainability aspect in the NICOLE Working Group Sustainable remediation;

5. Adopt the issue “remediation of large quantities” in the NICOLE Working Group Brownfields; 6. Do not develop additional tools (matrix, decision support tool etc.).


4. Overall conclusions

In general the Technical Meeting is considered a good tool to share knowledge on specific technical issues. Especially the subject of emerging contaminants has been effectively explained by the presentations and the discussion. The meeting urged attendees to take notice of and act upon the gained knowledge the day they return in the office. Also the conclusion of the afternoon “we know a lot” is valuable in itself.

Most of attendees’ expectations were met. Especially the review of projects is appreciated. The aim of the interactive sessions could have been made clearer, though the outcome is valued and satisfactory in the end. The follow up of the meeting will be eagerly watched by the members of NICOLE.


Appendix 1. List of participants NICOLE Technical Meeting on 4 November 2010

Argyrou, Elli Adventus Europe Greece Bakker, Laurent Tauw BV NL Beuthe, Birgitta SPAQuE Belgium Blom, Marianne ENVIRON Corporation NL Buvé, Lucia UMICORE Belgium Chippendale, Ruth Shell Global Solutions UK Clayton, Richard WSP UK Conder, Jason ENVIRON USA Couto, Felipe Remedx UK Croze, Véronique ICF Environnement France Darmendrail, Dominique BRGM France D'haene, Siegfried DEC Deme Env. Contractors NV Belgium Euser, Marjan NICOLE Secretariat NL Evans, Frank National Grid Property Ltd. UK Gehrels, Hans Deltares NL Gevaerts, Wouter Arcadis Belgium NV Belgium de Groof, Arthur Grontmij NL Groot, Hans Deltares NL Grundfelt, Bertil KemaktaKonsult AB Sweden Haerens, Bruno URS Belgium Belgium van Hattem, Willem Port of Rotterdam NL Henssen, Maurice Bioclear BV NL Iung, Olivier Antea France Jacquet, Roger Solvay S.A. Belgium Keuning, Sytze Bioclear BV NL Kirkebjerg, Kristian Grontmij-Carl Bro Denmark MacKay, Sarah WSP Environmental UK Maurer, Olivier CH2M Hill France Spain van de Meene, Chris SBNS NL Menoud, Philippe DuPont de Nemours Switzerland Merly, Corinne BRGM France Mezger, Thomas Akzo Nobel T&E bv NL Montchanin, Bertrand Shell France Mueller, Jim Adventus Europe Austria Muguet, Stephane MWH Belgium Müller, Dietmar Environment Agency Austria van Nieuwenhove, Karel Soresma Belgium Norström, Karin IVL - Swedish Env. Research Institute Sweden Ooteman, Kevin MWH NL Pals, Jan SBNS NL Pijls, Charles Tauw NL Quint, Mike Environmental Health Sciences UK De Ren, Luc Eurofins Analytico Belgium van Riet, Paul Dow Benelux BV NL de Rijk, Jaap MWH NL Ross, Ian ARCADIS UK Schelwald-van der Kleij, Lida NICOLE ISG Secretariat NL Sévêque, Jean-Louis UPDS France Shoesmith, Colin National Grid Property Ltd. UK Sinke, Anja BP International UK


Slenders, Hans Arcadis NL Van De Steene, Joke DEC Deme Env. Contractors NV Belgium Strandberg, Johan IVL - Swedish Env. Research Institute Sweden Sumann, Matthias Regenesis Germany Turland, Mike Vinci Construction UK Undi, Tilly Total UK Ltd. UK Vanhove, Bart CH2M Hill Belgium Belgium Visser-Westerweele, Elze-Lia NICOLE SPG Secretariat NL Waters, John ERM UK Wiltshire, Lucy Honeywell UK

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