News (2005)

21st December 2005 - Paul Grimwood

Quintessa is pleased to welcome Paul Grimwood as an Associate Consultant. Paul has extensive experience of low level radioactive waste management, including acting as Technical Manager for the Drigg facility in West Cumbria.

15th December 2005 - Visit by Dr Shang Zhaorong of the Nuclear Safety Centre, China

Dr Shang Zhaorong of the Nuclear Safety Centre in China recently spent two weeks at Quintessa's Henley-on-Thames office under the auspices of the IAEA and the British Council. The purpose of the visit was training and support in the application of AMBER to verify the safety and environmental impact assessment for the Chinese Beilong LILW near-surface disposal facility as part of its license application for commercial operation. The photograph shows Dr Shang working with Richard Little and Russell Walke to develop a conceptual and mathematical model of the Beilong site.

25th November 2005 - Alan Paulley joins the University of Edinburgh's Civil and Environmental Engineering Industrial Advisory Board

Alan Paulley has accepted an invitation from the University of Edinburgh to join the Civil and Environmental Engineering Industrial Advisory Board. The board provides guidance to and analysis of the curriculum and research aims of the faculty, thereby setting the tone for teaching and research associated with civil and environmental engineering in Scotland. For example, the most recent meeting provided useful recommendations concerning the importance of risk management and sustainability within the curriculum. Other organisations involved include senior members of Carillion, ARUP, Babtie Group, Sir Robert McAlpine Ltd, Taylor Woodrow Group, AWG Construction Ltd, Scottish Water Strategic Partnership, Network Rail, Montgomery Watson, Halcrow Waterman Ltd, Mott MacDonald, Powell Williams & Partners, Adept Knowledge Management, Carl Bro, and the Scottish Executive. For further information, please contact Alan Paulley.

23rd November 2005 - Facilitation support for CoRWM

Quintessa is currently providing assistance to Catalyze Limited in the provision of facilitation support to the Committee on Radioactive Waste Management (CoRWM). The terms of reference for CoRWM require the committee to review the potential options for managing UK radioactive wastes and to recommend an option, or combination of options, that will protect people and the environment.

The final stage of Catalyze's work with Quintessa is taking place in December, through a series of specialist workshops that will deliver 'scores' for different long-term management options, for different waste categories, against the scales for different criteria that were defined earlier in the process. Quintessa is providing a facilitator and recorders for these final workshops, helping to ensure that the integrity of the process is maintained and that the evidence and rationales for judgments made in the scoring process are captured and recorded.

In the new year, following completion of the 'specialist strand' of CoRWM's work, it is planned that Quintessa will continue to provide facilitation support to the committee, through its Integration working group. During this final phase of CoRWM's overall programme, it is necessary to bring together the various outputs that have been delivered through various aspects of the committee's work over the last two years. Quintessa will assist in this process, with a particular emphasis on providing support in the area of multi-criteria analysis and its integration into the committee's decision making.

For more information, please contact Mike Egan.

23rd November 2005 - Dounreay Shaft Isolation Project: Groundwater Modelling

Quintessa and URS Corporation have been awarded a contract to develop groundwater flow models in the vicinity of the D1225 Shaft at Dounreay, a historic facility for Intermediate Level radioactive Waste (ILW). These models will support the Post-Closure Safety Case for the Shaft following retrieval of the waste by feeding in to the revised hydrogeological conceptualisation at the district, site and shaft scales, recently constructed by Quintessa. The models will also act as predictive tools to assist in the design and installation of a low permeability grout curtain around the Shaft. The groundwater models will be developed on two length scales:

• a 'district' scale model of the Dounreay site catchment area; and
• a 'local' scale model of the area immediately surrounding the Shaft.

The models will be constructed using the state of the art groundwater flow and transport modelling package 'FEFLOW'. For more information, please contact Sarah Watson or Alex Bond

11th November 2005 - Quintessa Responds to the NDA Consultation on its Draft Strategy

Quintessa has responded to the consultation exercise for the draft strategy of the Nuclear Decommissioning Authority (<www.nda.gov.uk>.)

A copy of Quintessa's response can be downloaded here. For more information, please contact Alan Paulley

11th November 2005 - TESLA now available for download and online purchase

TESLA, Quintessa's software tool designed to aid the process of complex decision making, is available to download as a restricted trial version from the new-look TESLA website <http://www.quintessa-online.com/TESLA/> .  This restricted version is completely free and allows the user to:

• construct new decision trees with a limit of 10 sub-hypotheses;
• view decision trees saved by a licensed copy of TESLA;
• produce various plots to analyse the decision;
• print out decision trees and plots;
• try out all of the available propagation methods, including Evidence Support Logic (ESL) and Multi-Attribute Analysis (MAA).

In addition, a full licence can now be purchased over the website using secure credit card payments powered by PayPal <http://www.paypal.com> .  A licensed version of TESLA unlocks all of the restrictions of the trial version, allowing you to construct decision trees of any size and edit existing trees.

If you already own a TESLA licence you can log in to the website, edit your details, view your licence, renew it or purchase extra propagation methods for it.

For more information about TESLA, please contact tesla@quintessa.org.

18th October 2005 - SimER: An Advanced Computer Code for the Simulation of Environmental Risks

At the recent 10th International Conference on Environmental Remediation and radioactive Waste Management (ICEM) held in Glasgow, Scotland, Philip Maul presented the following paper on the SimER code:

Maul P R, Benbow S J, Bond, A., Kwong, S., Paulley, A., Penfold J S S, Robinson P C, Walke R C, Watson C E and Watson S P, “SimER: An Advanced Computer Code For The Simulation Of Environmental Risks Associated With Site End Points. Paper1097.

Quintessa developed the models in SimER and implemented these in software. Extracts from the paper submitted to ICEM are given here; the full final version will appear in due course in the conference proceedings.

SimER (Simulation of Environmental Risks) was developed over a four-year period, and the first version was released in June 2004. It has been designed for application in assessments of environmental remediation and other end points associated with contaminated land, and performance assessments for radioactive waste disposal. SimER represents a major advance in safety assessment modelling. It offers a unique range of functionality that, until now, has not been available in any single safety assessment tool. For the first time in a single application, it is possible to define a fully probabilistic three dimensional physical representation of an evolving landscape and engineered features, compute water and gas flows, model chemical reactions, calculate contaminant transport and evaluate a wide range of impacts. The capability to represent environmental change explicitly is particularly important for problems where impacts to humans and the environment may not occur for extended periods. Modern computing power,coupled with efficient model algorithms, means that complex environmental systems can now be assessed for periods of thousands of years in a few tens of minutes.

SimER is a powerful Performance Assessment (PA) code. The code was developed by Nexia Solutions Ltd, part of the BNFL group, and Quintessa Ltd. The SimER code was developed in line with the development of an integrated framework for site end point management.

The code has been developed to undertake assessments of both contaminated land and near-surface repositories. It therefore represents a major new tool to help address and assess issues on UK and other nuclear sites. Its main capabilities can be summarised as follows:

• The whole system can be modelled in a single code. This avoids the need for the output from one code to be used as the input to another. This greatly speeds up the assessment process and has major Quality Assurance advantages.
• Topographical details and geological structures can be represented.
• The evolution of the system with time is modelled explicitly.
• Groundwater flow and contaminant transport are represented using a 3D 'coarse' continuum approach
• SimER has a multiple run capability. This enables both sensitivity studies and probabilistic assessments to be undertaken.
• Both radioactive and non-radioactive contaminants can be modelled.
• The code includes a groundwater flow component, enabling groundwater flows to be calculated within the code rather than having to be imposed.
• The inclusion of a groundwater flow component, enables groundwater flows to be calculated within the code rather than having to be imposed.
• All model parameters have associated units, and SimER checks that all expressions and algorithms that are used have consistent units. This checking
• The code uses file-based input and output and enables data libraries to be included in code input.
• Graphical spatial viewers and parameter charter visualisation tools allow inputs and outputs to be checked visually.

For more information, please contact Philip Maul.

18th October 2005 - Preliminary Post-Closure Safety Case for the Dounreay Shaft

At the recent ICEM05 conference, James Penfold presented a paper [*] on the preliminary post-closure safety case for the Dounreay shaft.

The D1225 Shaft at Dounreay was authorised for the disposal of low and intermediate level radioactive waste in 1958. It lies close to sea cliffs on the north-western edge of the site and is 65 m deep, with a diameter of 4.6 m. Over 800 m3 of waste was disposed to the Shaft, the majority during the 1960s. All disposals ceased in 1977 following a hydrogen gas explosion that occurred in the headspace above the waste. The facility has since been maintained in a state of Care and Maintenance.

UKAEA has concluded that the retrieval of the waste is required to ensure that the Shaft can be closed safely, and detailed technical studies have investigated how this can be achieved. These studies identified that the Shaft needs to be hydraulically isolated from the surrounding rock and that a concrete plug at the base of the facility should be reinforced. A systematic examination and appraisal of the relevant technical options identified a preferred method for hydraulic isolation and plug reinforcement, based on the use of rock grouting.

Before commencing with detailed design and implementation of grouting works, UKAEA has undertaken a comprehensive analysis of the safety of the closed Shaft, which has resulted in the production of a Preliminary Post-Closure Safety Case (Preliminary PCSC). The main objective of the Preliminary PCSC is to provide robust arguments that the residual contamination around the Shaft will not result in unacceptable effects on human health and the environment, and thereby permit the next phase of closure activities to proceed. Regulatory guidance defines the information that is expected in a PCSC; however, this is primarily for use in the authorisation of new disposal facilities. Nevertheless, the Preliminary PCSC for the Shaft comprises a suite documents addressing the requirements of this guidance.

The Main PCSC Report describes twenty key factors that constitute UKAEA's safety case for the closed Shaft. These safety factors are based on the scientific and technical understanding of the system and draw on a supporting performance assessment study. They are both qualitative and quantitative, and are diverse in nature. Together, they provide 'multiple lines of reasoning' that support the case for post-closure safety.

The Main Report is supported by six other reports. Three describe what is known about the radioactive contamination around the Shaft, and the characteristics of the facility and its environment. A detailed performance assessment of long-term safety is reported, using modelling tools founded on this information. The options for the closure state of the Shaft are also examined in a supporting report, and a further document describes how the closure of the Shaft will be managed.

The Preliminary PCSC has been submitted to the regulatory authorities for review, and is also undergoing independent peer review. Periodic revisions to the PCSC will be driven by regulatory milestones, the availability of new information and other external changes, such as national policy developments.

For more information, please contact James Penfold.

[*]	James Penfold, Warren Jones and Michael Tait. Preliminary Post-Closure Safety Case for the Dounreay Shaft. ICEM'05: The 10th International Conference on Environmental Remediation and Radioactive Waste Management September 4-8, 2005, Scottish Exhibition & Conference Centre, Glasgow, Scotland.

12th October 2005 – Free Downloadable Version Available for the AMBER Compartment Modelling Software

A freely downloadable demonstration version has been developed for the AMBER compartment modelling software that Quintessa supports in collaboration with Enviros Consulting Limited. The Demonstration Version provides potential AMBER users with a restricted version of the software that demonstrates AMBER's capabilities.

The Demonstration Version includes instructions for creating an AMBER case file from basics. In addition to the tutorial, the demonstration is accompanied by the following six simple example AMBER cases, further illustrating some of AMBER's capabilities and including a restricted capacity for modification:

• an implementation of a model developed for use within an International Atomic Energy Agency (IAEA) training course on Safety Assessment of Near Surface Low and Intermediate Level Radioactive Waste Disposal Facilities;
• an implementation of Example Reference Biosphere 2A, produced within the IAEA's Biosphere Modelling and Assessment (BIOMASS) program;
• an implementation of a model developed by Nuclear Energy Agency for the inter comparison of assessment codes, "PSACOIN 1B";
• a simple model of C 14 migration in an aquatic system;
• a biokinetic model for lead behaviour in the human body; and
• a simple model incorporating a Gaussian plume model within an atmospheric deposition source term (file R91.cse).

The installation includes a User Manual that provides some background to AMBER, gives detailed step-by-step instructions for developing the demonstration tutorial case and briefly describes the example cases.

Click here to be taken to the download page, which is hosted on the Quintessa-online website. For more information, please contact Russell Walke.

11th October 2005 - Waste Package Scenario Modelling

At the recent 29th International Symposium on the Scientific Basis for Nuclear Waste Management in Belgium (MRS 2005), Sarah Watson presented an overview of work for UK Nirex on waste package scenario modelling.

Nirex has supported a programme of work to develop models describing the post-closure evolution of intermediate-level waste packages with the objectives of:

• providing support and justification for the parameters and representations used in performance assessment models;
• informing future model development and packaging advice.

Scenarios for the potential evolution of a waste package were developed and modelled taking explicit account of waste package heterogeneity and the time-dependence of the physical and chemical characteristics of the system. The modelling work highlighted the treatment of organic complexants and the representation of physical containment as two areas in which the impacts of time dependence and package scale heterogeneity might be particularly significant. A further study of the impact of organic complexants emphasised the importance of heterogeneity in package inventory in determining the radionuclide release from the near field.

The degree of containment afforded by the waste form and the waste container has been investigated as part of a study to develop a preliminary understanding of the mixing scales within the repository. The study suggests that the most important control on the release of radionuclides from the waste packages is the integrity of the waste encapsulation grout. Interactions between neighbouring packages are to be expected but the degree to which homogeneous (well mixed) conditions develop may be limited in both time and space.

For more information, please contact Sarah Watson.   

29th September 2005 - Radioactive Waste Management: A Participatory Approach to Increase the Influence of Local Actors on the National Decision-Making Process

At the recent ICEM05 conference, Mike Egan presented a paper [*] elaborating upon a participatory methodology to pursue the objective of studying and defining mechanisms for local actors to 'stretch' national players in decision making for radioactive waste management. This paper describes work in progress for one of four work packages constituting the COWAM 2 European 6th Framework research project, which runs from January 2004 to the end of 2006. The work encompasses three consecutive tasks:

• Focusing on local-national relations through the study of specific current situations in France, Spain and the UK;
• Working out possible mechanisms for an effective local influence on national decision processes;
• Reflecting upon the balance of power in local-national relationships.

The project is working within a framework set by stakeholders, who have defined the case studies in progress and established success criteria for the work. This has been accomplished in part through workshops in which more than 20 stakeholder representatives, constituted as a 'reference group', have been involved. The same collaborative approach will continue throughout the project.

For more information, please contact Mike Egan.

[*]

Raul Espejo, Michael Egan, Gilles Heriard-Dubreuil and Mariano Vila d'Abadal. Radioactive Waste Management: A Participatory Approach to Increase the Influence of Local Actors on the National Decision-Making Process. 10th International Conference on Environmental Remediation and Radioactive Waste Management, ICEM05, Glasgow, September 2005, Paper 1314

29th September 2005 – Independent Review of Tasks 6A, 6B and 6B2 of the Äspö Task Force on Modelling of Groundwater Flow and Transport of Solutes

An independent review is being carried out of the specifications, execution and results of Task 6 of the Äspö Task Force on Modelling of Groundwater Flow and Transport of Solutes, which is seeking to provide a bridge between site characterization and performance assessment approaches to solute transport in fractured rock.

A review of sub-tasks 6A, 6B and 6B2 has recently been published [1], related to the transport of tracers on a 5-metre scale in Feature A at the TRUE-1 site.

The task objectives, specifications and individual modelling team results were summarised and reviewed, and an evaluation of the overall exercise was presented. The report concludes with assessments of what has been learnt, the implications for the Task 6 objectives, and some possible future directions.

26th September 2005 - House of Commons Select Committee on Science and Technology: Carbon Capture and Storage (CCS) Technology

The House of Commons Select Committee on Science and Technology has invited evidence on:

• The viability of CCS as a carbon abatement technology
• The UK Government's role in funding CCS R&D and providing incentives for technology transfer and industrial R&D

In response to this request, Quintessa has submitted written evidence to the committee. This highlights the need for continued R&D related to the assessment of the long-term impacts of potential leakages from CO2 geological storage, and the need to establish an appropriate regulatory regime.

Please click here for a copy of Quintessa's written evidence.

For further information, please contact David Savage.

22nd August 2005 – Quintessa Opens Warrington Office

Quintessa is pleased to announce the opening of a new office in Warrington initially staffed by Mike Egan, Alan Paulley and Alex Bond. The Warrington office provides a convenient base for work relating to Nuclear Decommissioning and Site Restoration. In particular the office is able to provide support to the Nuclear Decommissioning Authority and nuclear site licensees in the management of the UK's nuclear legacy through:

• Decision-making, BPEO and BPM
• Site end point development
• Data interpretation and visualisation
• Geology and hydrogeology
• Environmental risk assessments
• Mathematical Modelling

For more information, please contact: Mike Egan – MikeEgan@quintessa.org +44 (0)1925 885953 Alan Paulley – AlanPaulley@quintessa.org +44 (0)1925 885952 Alex Bond – AlexBond@quintessa.org - +44 (0)1925 885951

22nd August 2005 – Alex Bond joins Quintessa

Quintessa is pleased to welcome Alex Bond to the new Warrington office. Alex has a BA and MA in Earth Sciences and an MSc and PhD in Hydrogeology. Both through his academic training and recent experience on a variety of NDA sites, Alex has developed extensive experience of the conceptualisation and numerical modelling of geological and hydrogeological systems, especially with regard to contaminant fate and transport modelling and environmental risk assessments. Alex was heavily involved in the production of the recent post-closure safety case for the Drigg LLW disposal facility, and has acted as a key technical lead for much of the contaminated land and waste facility assessment work conducted on Sellafield and Springfields sites. Alex has considerable experience of scientific code development, and is well versed in the application of a variety of tools, including MODFLOW, NAMMU, TRAFFIC, AMBER, GoldSim, ArcGIS and various visualisation packages.

22nd August 2005 – Alan Paulley joins Quintessa

Quintessa is pleased to welcome Alan Paulley to the new Warrington office. Alan trained in Chemical Physics at the University of Sheffield and gained his PhD in the theory of conducting polymers at the same university. He then joined BNFL where, over a period of eight years, he led a number of technical areas and projects, and was one of the authors of the 2002 Drigg Post-Closure Safety Case. Alan was also a key contributor to a range of projects supporting NDA sites, in particular Sellafield, and has particular experience in developing solutions directly for the NDA underpinning the derivation and assessment of site end points and strategies.

20th July 2005 - Issue profile: environmental issues and the geological storage of CO₂

The British Geological Survey and Quintessa have recently published a position paper highlighting environmental issues associated with the geological storage of CO₂.

The background to this is that increasing CO₂ emissions will lead to climate change and ocean acidification with severe consequences for ecosystems and for human society. Strategies are being sought to reduce emissions including the geological storage of CO₂.

Existing studies operate within existing oil and gas regulatory frameworks, but if other non-oil reservoir geological formations are used these existing regulations may not apply. At UK and European levels the potential environmental impacts of uncontrolled CO₂ releases from storage sites have been highlighted to be of significance for regulators. Thus a new regulatory framework may be needed.

The precautionary principle is likely to be adopted by regulators, so it is important that the effects of acute and chronic exposures of ecosystems to CO₂ leakages are evaluated. Consequently, existing regulations are likely to be developed to include specific recommendations concerning leakages. This review shows that many basic data simply do not exist to assist regulators in this process.

To download a copy of the paper, please click here.
Copyright © 2005 John Wiley & Sons, Ltd and ERP Environment.

For more information please contact Philip Maul.

6th July 2005 – Physical Integrity of AGR Graphite Cores

Demonstrating the maintenance of the physical integrity of graphite cores in Advanced Gas Cooled Reactors (AGRs) is a critical part of the safety case for their operation. Quintessa is providing support to British Energy in a number of key areas associated with the development of defects in the graphite bricks as they age, and predictions of the evolution of graphite properties with time. Advanced statistical methods have been used to enable the safe period of reactor operation to be calculated on the basis of the history of brick defects observed to date, and to determine the optimum future monitoring strategy. These methods will be applied to each of the reactors when they are shutdown for inspection.

For more information please contact Philip Maul.

27th June 2005 – Quintessa Responds to 2nd Consultation Document from CORWM: How Should the UK Manage Radioactive Waste?

The Committee on Radioactive Waste Management (CORWM) has been appointed by the UK Government and the devolved administrations for Scotland, Wales and Northern Ireland to review the potential options for managing UK radioactive wastes and recommend an option, or combination of options, that will protect people and the environment.

In April 2005, CORWM issued a 2nd consultation document as part of its programme of public and stakeholder engagement requesting feedback on:

• CORWM's proposed short-list of waste management options;
• CORWM's proposed process and criteria for assessing the short-listed options; and
• What matters to the public and stakeholders about the way in which the options CORWM will recommend should be implemented.

As a leading radioactive waste consultancy, Quintessa has submitted a response to the consultation with aim of helping the Government to develop a well-founded, robust and coherent basis for the long-term management and disposal of radioactive wastes. To download a PDF file of Quintessa's response, please click here.

For more information please contact David Hodgkinson.

16th June 2005 - PRISM foodchain modelling presented at SRP symposium

The UK Society for Radiological Protection (SRP) recently held its Seventh International Symposium in Cardiff, focusing on 'Change and Continuity in Radiation Protection' (12th to 17th June, 2005). The symposium attracted many participants from around the globe and included sessions devoted to a broad scientific content, covering topics from fundamental radioecology to instrumentation. Russell Walke attended the conference for Quintessa and presented an oral paper and two poster papers relating to the recent development of updated foodchain models for the UK Food Standards Agency (FSA) and their implementation into the PRISM 2.0 software. Other members of the PRISM development team include Philip Maul (project management), Mike Thorne (model development), Peter Robinson and Claire Watson (both software implementation).

PRISM provides the FSA with the capability to model radioactive and non-radioactive contaminants in the foodchain for complex agricultural scenarios following short and long-term routine and accidental atmospheric releases. The revised soil, plant and animal models are backed up with a review of the latest radioecological research. The probabilistic models are implemented in a wrapped version of AMBER, with the parameters being specified in an Access database and the user interactions managed via a new graphical-user interface.

For more information about PRISM, please contact Philip Maul.

3rd May 2005 - Post-Closure Safety Case for the Dounreay Shaft

The ILW Shaft at Dounreay contains around 850 m³ of intermediate level radioactive waste, consigned in the 1960s and early 1970s. The historic facility does not meet modern safety standards, therefore UKAEA intends retrieving the waste for more suitable management so the Shaft can be safely closed. This requires the facility to be isolated from surrounding groundwater. UKAEA proposes to do this by sealing the rock around the 65 m deep Shaft with cement-based grout, a major engineering project.

Before commencing rock grouting, UKAEA has been required by regulators to assess the long-term safety of the proposed approach. UKAEA contracted Quintessa to develop a detailed Post-Closure Safety Case (PCSC) for the remediated Shaft, and undertake a range of supporting studies. This included a detailed re-evaluation of geology, hydrogeology and geochemistry; an assessment of Shaft closure options; a review of the inventory and a safety assessment. In addition, summary and overview documents were produced. The suite of seven documents –comprising more than 800 pages – has been successfully submitted to regulators. UKAEA is now beginning rock grouting trials. The PCSC will be periodically updated to benefit from information gained from UKAEA's ongoing research of the Shaft environment.

For more information please contact James Penfold.

20th March 2005 - Radioactively Contaminated Land – Development of 'RCLEA' Model

The UK Government's Department of the Environment, Food and Rural Affairs (Defra) is developing a regime for the regulation of radioactively contaminated land in the UK that is expected to come into force in the next year or so. The regime will focus on historic contamination where there is a potential need for intervention actions to reduce or avert radiation doses. It does not cover contaminated land on nuclear licensed sites.

Defra has commissioned Quintessa, supported by URS Corporation, to develop a 'Radioactively Contaminated Land Exposure Assessment' (RCLEA) model for quantitative risk assessment. It will complement the existing 'CLEA' model for non-radioactively contaminated land. The project will involve the development of documentation and associated computer models. The proposed approach will be consulted upon in late May and June 2005 (details will be available at www.safegrounds.com). The finalised methodology will be available in early 2006.

For more information please contact James Penfold.

2nd February 2005 - Building Confidence in Geological Models

A paper by Andrew Bowden, a Quintessa Associate Consultant, describing an evidence-based uncertainty analysis framework for building confidence in geological models has been published in a special publication of the Geological Society of London entitled Geological Prior Information: Informing Science and Engineering. The analysis makes use of Quintessa's TESLA decision support modelling application based on Evidence Support Logic. For a reprint of the paper please contact Andrew Bowden. For further information about TESLA, please contact tesla@quintessa.org.

1st February 2005 - New EuropeAid PHARE contract

Quintessa has been awarded a contract under EuropeAid's PHARE programme to produce a preliminary safety analysis report (PSAR) for the Baita Bihor low-level radioactive waste repository in Romania. The contract is due to be completed in August 2006.

Quintessa with be supported by a team of sub-contractors including: the Subsidiary of Technology and Engineering for Nuclear Projects (SITON) (Romania); Mike Thorne and Associates Limited (UK); Geo Prospect S.R.L. (Romania); and IC Consultants Limited (UK).

For more information, please contact Richard Little.

Project financed by EUROPEAN UNION

The European Union supports Romania with expertise and financial resources in view of accession preparation, through three specific programmes: Phare, Ispa and Sapard. The beneficiary sectors vary from regional development and SME support, to investments in transport and environmental infrastructure and rural development. The total annual amount of funds allocated to Romania through the three pre-accession programmes is increasing from about 660 MEURO in 2003 to well over 1 billion in 2006. The management of these funds is done by the Romanian authorities, under the coordination of the Ministry for Public Finance.

7th January 2005 - Sequestration of CO₂ in geothermal areas

Quintessa is providing numerical modelling support to a project investigating the feasibility of sequestering atmospheric CO₂ in geothermal areas. This sequestration strategy is one possible means for mitigating the effects of climate change caused by anthropogenic CO₂ emissions. The work is being carried out in collaboration with Mitsubishi Materials Corporation (MMC), the Research Institute of Innovative Technology for the Earth (RITE) and the Central Research Institute of Electric Power Industry (CRIEPI). Funding is being provided by Japan¹s New Energy Development Organisation (NEDO).

A potential advantage of sequestering CO₂ in geothermal areas, where high temperatures (to several hundred °C) occur, is that reactions between CO₂-charged water and rock will be more rapid than in rocks at lower temperatures. In turn these reactions could potentially favour the trapping of CO₂ in solid mineral phases such as calcite. To evaluate the feasibility of this sequestration option the coupled flow-reaction processes that would accompany CO₂ injection must be understood. If the reaction rates are too fast and the rocks¹ porosity and permeability decrease near to the CO₂ injection point, further CO₂ injection might be prevented. On the other hand, if reactions are too slow or porosity increases too much, then injected CO₂ might migrate too far and leak from the rock reservoir.

Quintessa has evaluated various aspects of this coupling, by theoretical modelling using a combination of widely used geochemical simulation codes (PHREEQC and Geochemist¹s Workbench) and Quintessa¹s own Raiden3. Raiden3 fully couples simulations of flow and reactions while taking into account reaction kinetics. One application of Raiden3 in the present project has been to develop an improved understanding of the processes that occur during the migration of CO₂-saturated water through granodiorite at 200°C and 100 bars.

For more information please contact Richard Metcalfe.