In June 2009, the 5-year multi-national project EURANOS, funded by the EuropeanCommission in its 6th Framework Programme, reached its end, achieving most of theobjectives addressed in the work programme. Partners from 23 European countriesintegrating 17 national emergency management organisations with 33 research institutes,aimed to enhance the preparedness for Europe’s response to any radiation emergency andlong term contamination. Three handbooks to assist national and local authorities in themanagement of contaminated food production systems, inhabited areas and contaminateddrinking water resources in Europe were developed in conjunction with a wide range ofEuropean stakeholders. Further guidance was prepared to support the decision making teamin the lifting of early phase countermeasures. A governance framework for the sustainablerehabilitation of long term contaminated territories was developed and tested in Franceand in Norway. Considerable progress was made in developing a consistent set of models forcalculating the best estimate of the current radiological situation in both contaminatedagricultural and inhabited areas. These models were integrated in both the ARGOS and theRODOS decision support systems. Decision aiding components were improved to support theselection of management options with the help of multi criteria decision analysisprocedures. A mass consistent wind field model was implemented together with a particlemodel for complex terrain. The migration of RODOS (Real-time On-line Decision SupportSystem) to the operating system LINUX was completed. RODOS was completely re-engineered,taking into account the users’ recommendations from the demonstration projects andfeedback from its operational use. This new version will build the kernel for theoperational RODOS release in 2010 and new research activities related to the futureimprovement of RODOS.

Three handbooks have been developed, in conjunction with a wide range of stakeholders toassist in the management of contaminated food production systems, inhabited areas anddrinking water following a radiological incident. The handbooks are aimed at national andlocal authorities, central government departments and agencies, emergency services,radiation protection experts, the agriculture and food production sectors, industry andothers who may be affected. The handbooks include management options for application inthe different phases of an incident. Sources of contamination considered in the handbooksinclude nuclear accidents and radiological dispersion devices; the most relevantradionuclides are included. The handbooks are divided into several sections which providesupporting scientific and technical information; an analysis of the factors influencingrecovery; compendia of comprehensive, state-of-the-art datasheets for around 100management options and guidance on planning in advance. A decision-aiding frameworkcomprising colour coded selection tables, look-up tables and decision trees and severalworked examples are also included. The handbooks can be used as a preparatory tool, undernon-crisis conditions, to engage stakeholders and to develop local and regional plans. Thehandbooks can also be applied as part of the decision-aiding process to develop a recoverystrategy following an incident. In addition, the handbooks are useful for trainingpurposes and during emergency exercises. To realise their full potential, the handbooksshould be customised at national, regional and local levels.

Generic guidance on the withdrawal of sheltering, withdrawal of evacuation and evacuationof sheltered populations (displacement) has been developed based on previously unpublishedwork in the UK and France and on input from stakeholder panels in Germany, Belgium, Franceand the UK. The guidance is a living document that can be developed further in the future,both in its generic form and also as customised versions in some Member States. Theguidance outlines the many factors which influence the withdrawal of emergencycountermeasures: official confirmation that any release has stopped; adequacy ofmonitoring data; radiological criteria; radiological protection advice; availability ofresources; social and psychological needs; stakeholder dialogue; and communicationstrategy. The relative importance placed by decision makers on each of these criteriawould vary according to the nature and scale of the accident and also on socio-political,economic and cultural perspectives. In the event of a radiological incident, decisionmakers will need to be in a position to construct a strategy for managing the withdrawalof emergency countermeasures. For larger scale, longer duration releases involving severalnuclides, a management strategy is likely to be complex. The guidance therefore includes aseries of checklists which have been developed in conjunction with stakeholders to takeinto account the main criteria and factors which should be considered.

The research activities under the work package CAT2 – improvement of decision supportsystems, focused on the one hand to improve the operability of the RODOS system but on theother hand to enhance RODOS and ARGOS with simulation models still missing in theportfolio of these two decision support systems. For RODOS, the work focused on theimprovement of the atmospheric dispersion modelling in complex terrain and the improvementof the data assimilation functionalities. For both systems, the later phase models dealingwith countermeasures in inhabited areas and food production systems have been considerablyenhanced.

The European Model for Inhabited Areas (ERMIN) was developed to explore recovery optionsfollowing the contamination of an urban environment with radioactive material. This paperdiscusses the user experience of ERMIN and in particular it concentrates on thedevelopment of a description of the urban environment and how that description affects theoutput. The user interacts with ERMIN by defining different regions on a map. A region maybe an area in which a particular combination of recovery countermeasures is applied, orwhere a particular level of contamination is found, or where there is a particular type ofurban environment. Most of the output from ERMIN is also presented as maps with summaryinformation that allows the user to compare different countermeasure strategies. ERMIN hasbeen implemented within two international nuclear accident Decision Support Systems; RODOSand ARGOS. Both systems have user interfaces that exploit geographic information system(GIS) technology which complement the ERMIN map based approach.

Predictions of the effects of agricultural countermeasures are an important part of thedecision-making process following an accidental release of radioactive material into theenvironment. A new model has been developed for this purpose and integrated into the EUdecision support systems RODOS and ARGOS. The model is based on the existing food chainmodel of RODOS and the previous model for simulating agricultural countermeasures inRODOS. The characteristics of the countermeasures and the supporting databases have beenderived from the compendia and handbooks developed within the EURANOS project. A widerange of potentially practicable countermeasures is considered on timescales from a day tomany years, and endpoints related to their imposition are calculated such that theeconomic and health impacts can be evaluated. This paper outlines the countermeasuresmethodology adopted and the databases used and discusses their applicability.

The Meteorological Pre-Processor (MPP) of the Decision Support System RODOS acts asinterface between the incoming meteorological data from stations and/or prognostic modelsand the Atmospheric Dispersion Models (ADMs) used for predicting the spread of theaccidentally emitted radionuclides. The MPP includes a diagnostic Wind Field Model (WFM)to ensure mass conservation of the calculated wind field. Its output is usable by simpleand complex ADMs and it is applicable for highly complex topography and from micro- tomeso-scales. The MPP has been tested for both real and artificial flow fields and it hasbeen optimized to function with very short execution times and to give the most reasonableresults under all terrain complexity and atmospheric stability conditions. DIPCOT(DIsPersion over COmplex Terrain) is a Lagrangian Puff / Particle model that has beenimplemented in RODOS to simulate radionuclides atmospheric dispersion over complicatedterrain. For this purpose, it uses a certain number of fictitious puffs/particles whichare assumed to move with the mean wind flow plus a random velocity component to simulateturbulent diffusion. The calculation of the gamma radiation dose rates in air due to theradioactive plume is calculated by a very fast method that takes into account theinhomogeneous 3-dimensional cloud shape. DIPCOT has been evaluated by comparisons towidely used real-scale experimental data sets: Copenhagen, Prairie Grass, Indianapolis andMol. The integration of the above models greatly enhances the applicability of the RODOSsystem.

The Multi-scale Atmospheric Transport and Chemistry Model (MATCH) is used in the RODOS(Real-time On-line decision Support) system since more than 10 years for the long rangeatmospheric transport and dispersion calculations. With the start of the EURANOS project,several functionalities of the model at that time should be further enhanced. Thisincluded the better use of the meteorological information available in the numericalforecast data and the coupling to the source term data base of the RODOS system.

During the EURANOS project three atmospheric dispersion models ATSTEP (ATSTEP, 2007),RIMPUFF (RIMPUFF, 1999), and DIPCOT (DIPCOT, 2009) used in the RODOS (Ehrhardt and Weis,2000) decision support system were subject of comprehensive comparison and validationstudies. The aim of the comparison exercise was a harmonisation of the models for a sampleof representative, non-complex dispersion and deposition situations in the distance rangebelow 100 km. Despite of different modelling and parameterisation the models shoulddeliver similar results under these conditions. Furthermore validation studies werecarried out with ATSTEP and DIPCOT using measured meteorological and contamination datafrom tracer dispersion field experiments. After minor model and parameter modificationsfinal comparison calculations of the models with realistic numerical weather prediction(NWP) data have shown satisfactory consistency of the results.

For four German nuclear power plant sites and for Risø, the site of the Danish nuclearresearch reactors now being decommissioned, Numerical Weather Predictions (NWP) of windspeed and direction have been compared to 10 minute averaged local measurements. For theGerman sites the comparison covers data for approximately three month, January to March2009, for the Risø site for approximately two thirds of the year October 1998 to September1999. For each site the comparison has been made for all measurement levels and both forthe NWP analysis time and for the maximum available forecast time. Means and standarddeviations of NWP minus measured data are given as tables for all measurement levels whilescatter plots are presented for only a single measurement level at analysis time at eachsite. For Risø and for the site close to the North Sea plus for the inland sitePhilippsburg the predictions of wind speed are on average rather close to the measured,but for sites not far from the latter two, Krümmel respectively Obrigheim, thediscrepancies are substantial.

Contemporary open source JAVA technologies implemented within the EURANOS project for thecross-platform re-engineering of the decision support system RODOS (JRODOS) were used alsoto redesign the Hydrological Dispersion Module (HDM) of this system. JHDM – thehydrological model chain of JRODOS contains models to simulate the radionuclide transportin the system “atmospheric fallout on watershed – river net” and calculate the doses viaaquatic pathways. JHDM used for this purpose a limited number of the input parameters tocharacterize the hydrological properties of the catchment/river network of interest. Thepilot implementation of JHDM for the Vistula river basin carried out by POLATOM andsupported by the national hydrological institute, demonstrated good perspectives of theapproach used in JHDM for the decision support in cases of accidental contamination ofwater systems. Particular needs for further improvements of the JHDM software system havebeen identified.

Within the EURANOS project data assimilation (DA) approaches have been successfullyapplied in two areas to improve the predictive power of simulation models used in theRODOS and ARGOS decision support systems. For the areas of atmospheric dispersionmodelling and of modelling the fate of radio-nuclides in urban areas the results ofdemonstration exercises are presented here. With the data assimilation module of theRIMPUFF dispersion code, predictions of the gamma dose rate are corrected with simulatedreadings of fixed detector stations. Using the DA capabilities of the IAMM package formapping the radioactive contamination in inhabited areas, predictions of a large scaledeposition model have been combined with hypothetical measurements on a local scale. Inboth examples the accuracy of the model predictions has been improved and theuncertainties have been reduced.

In nuclear and radiological emergency and post-accident management decisions oncountermeasures and remediation strategies have to be made. Whereas in the early phasedecisions on emergency actions must be made in a very short time, according to emergencyplans and dose thresholds, in the recovery phase complexity is higher. But there is alsomore time for evaluating alternative countermeasures and remediation strategies withrespect to several goals. In this paper evaluation strategies supporting the decisionmakers throughout all phases are presented. The applied decision support techniques rangefrom graphical presentations of decision relevant information about the alternatives foraction to multi-criteria decision making (MCDM) methods. In particular methods to copewith several types of uncertainties inherent in the different phases are presented. By theintegration of these techniques, the decision support system RODOS is able to providesupport for more conscious, transparent and coherent decision making.

One key issue in the EURANOS project was the methodological and technological improvementof decision support systems, in particular the RODOS system, with respect to the practicalapplication in operational emergency centres. The development process was mainly driven bythe result of demonstration activities and responses obtained from the end-users in theemergency centres. The intention of this article is to give an overview of all major workitems which have been performed within EURANOS with the aim of improving decision supportsystems. More details about several of these activities can be found in separate articlesin this issue.

Decision makers must react in a prompt and appropriate manner in various emergency situations. The bases for decisions are often predictions produced with decision support systems (DSS). Actual radiation measurement data can be used to improve the reliability of the predictions. Data assimilation is an important link between model calculations and measurements and thus decreases the overall uncertainty of the DSS predictions. However, different aspects have to be taken into account for the optimal use of the data assimilation technique: different countries may have differing measurement strategies and systems as well as differing calculation models. The scenario and the amount and composition of radionuclides released may vary. In this paper we analyse the situation during and after an accident and draw up a list of recommendations that can help modellers to take into account the measurements that are best suited for data assimilation.

The decision support system RODOS (Ehrhardt and Weis, 2000) contains a large set ofsimulation models, data bases, user interfaces and system functionalities. However thesemany options resulted in heavy-weight and complex user interfaces difficult to handle bynon-experts. For this reason a user friendly and light-weight access to the RODOSfunctionalities was requested by the end users. This was fulfilled by the design andimplementation of a new user interface named RODOS-Lite. The main purpose of thisredesigned user interface is to gently lead operators through a sequential line of inputmasks, hiding rarely used parameters (defaults are set) from the operator but stillproviding the possibility to access them if necessary. Additionally, the interface isstrongly safeguarded to prevent operators from entering wrong input values. This isachieved by systematically checking input values and even suggesting occasionally bestestimate parameters. RODOS-Lite is complemented by various simple but neverthelessextremely useful features such as online access to Google maps or source termvisualisation.

The ERMIN model is a new implement developed to enable estimation of the radiologicalconsequences in inhabited areas of accidents in nuclear installations. Similarly, AGRICPis a model developed to enable estimation of the radiological consequences ofcontamination of agricultural production areas. This paper provides a short overview ofthe background of the two models and describes the features enabled through theirimplementation in the ARGOS decision support system. The integration allows calculation ofboth dose rates and doses in particular areas, and can be used to evaluate theeffectiveness and costs of countermeasure strategies.

Experience following the Chernobyl accident in the CIS and the EU has clearlydemonstrated that policies and strategies for long-term management of extensivecontaminated areas must give due importance to social, cultural, ethical, environmental,economic and political factors beyond the sole radiological protection and healthperspective. What is at stake in the long-term response to such a situation is thesustainable rehabilitation of living conditions in affected territories, in a context inwhich each person can actively contribute to his own protection. Preparing or developingrehabilitation of living conditions in a territory affected by long-lasting radioactivecontamination is a broader issue of governance as it must address all affected dimensionsand articulate the actions of the various concerned actors at the local, regional andnational level. To respond to this challenge, a specific research project was implementedby Mutadis, CEPN, NRPA and AgroParisTech from April 2004 to June 2009 in the framework ofthe EURANOS integrated programme. The overall objective of this project was “todevelop a strategic and methodological framework that can inform or assist nationalauthorities in Europe in establishing arrangements for the long-term management and thesustainable rehabilitation of living conditions in extensive areas that may becontaminated as a result of an accident or malevolent act involving radioactivematerial”. The proposed framework describes a two-steps method allowingnational and local authorities together with key stakeholders to establish arrangementsand preparation strategies in the perspective of long-term management of a radiologicalevent. It may also be used to develop rehabilitation strategies in countries affected bylong-lasting radioactive contamination. This framework aims to set up favourableconditions for stakeholders (in particular local communities) to engage effectively andsustainably in the cooperative development of post-accident preparation or managementstrategies. The first step of the method aims to frame the issue and identify conditionsfor stakeholders to engage in rehabilitation preparedness or management strategies. Thesecond step aims to develop a local-national cooperation platform gathering local andnational, private and public actors to develop together preparation or managementstrategies.