The ECURIE Competent Authorities Meeting in February 2006 decided, in response to a proposal by the European Commission, that the Swedish FALKEN nuclear emergency exercise would also be the ECURIE main level 3 exercise in 2006. The FALKEN exercise was carried out on 4 October 2006. Sweden played the role of an accident country. The scenario for use in the exercise was chosen in such a way that a serious emergency happened at the Ringhals NPP Unit 1 (BWR).
The exercise involved the new version of the ENSEMBLE long-range atmospheric dispersion forecast system, managed at the JRC Ispra. It was the first application of version 2 of the system in such international exercise.
The ENSEMBLE activity, which is part of the Joint Research Centre (JRC) institutional support activity to DG-TREN, is described in detail in Galmarini et al. (2001), Galmarini et al. (2004a, b and c). It consists of a network of 19
countries and 22 institutions (mainly from Europe but also from US and Canada – see Appendix for the list) operating 24 long range atmospheric transport and dispersion models. The dispersion models used by the various institutions differ in terms of concept and numerical code and make use of weather forecasts produced by different Global Circulation Models or Limited Area Models. Once the network is alerted, the model predictions produced by the various institutions are collected on the ENSEMBLE system located at the EC/Joint Research Centre in Ispra. A web facility allows the remote users to consultant in real-time and independently the model results present on the system. In this way every participating institution has the possibility of comparing in-house model predictions with those produced by others and of assessing the reliability of model forecasts. Most of the institutes that constitute the ENSEMBLE network normally act as national scientific and technical advisors to decision makers in case of emergency. All the services provided by the ENSEMBLE system are in real-time. ENSEMBLE was already used successfully during other
international exercises such as CONVEX exercise in 2005, other ECURIE exercise in 2002, DSSNET exercise in 2003 and 16 periodic exercises performed since 2001. A dedicated site was created specifically for this exercise, where a synthesis of the various model results were presented to the outside world namely National Competent Authorities and advisors to decision makers that are presently not part of the ENSEMBLE activity and that have no access to the restricted site.
This report gives details on the contribution of ENSEMBLE to ECURIE exercise. Section 1 describes the organisation of the exercise events timeline, the notification procedure to the ENSEMBLE community, Section 2 contains information about the scenario and the source terms used for the simulation; Section 3 describes the public web site where the results of the ENSEMBLE analysis produced at JRC during the exercise were published in real-time; in Section 4 a summary is provided on the ENSEMBLE community response to the notification and on the dispersion forecasts produced during the exercise; Section 5 presents for each of the releases considered the results produced within ENSEMBLE which were not published on the public web site; and finally the conclusions are included in Section 6.
1. ORGANISATION OF THE EXERCISE AND ACTIVATION OF THE ENSEMBLE
As mentioned above in the ECURIE exercise Sweden played the role of accident state with Ringhals NPP as a localization of major radiological event.
According to agreed procedures on notification first, Sweden sent accident information to IAEA (ENATOM arrangements) and EC (ECURIE arrangements). The number of messages was fairly low and their
information content limited, but nevertheless sufficient to satisfy Council Decision 87/600/Euratom requirements at an early stage of the emergency. The first alert was received at the Commission security office in Brussels, which notified the TREN H.4 ECURIE duty officer in Luxembourg. Then the ECURIE duty officer activated the ECURIE communication room in Luxembourg and forwarded the message to all official stations in the CoDecS network and additionally by fax to all ECURIE contact points. The TREN H.4 emergency team collected the incoming information and used the available emergency tools (IAEA ENAC, EURDEP, ENSEMBLE and RESPEC) in order to assess the situation and provide information to TREN hierarchy and other Commission emergency services.
JRC REM group (JRC H.4) activated the ENSEMBLE system and maintained the website tool for displaying atmospheric dispersion forecasts produced by the system. Access info for this site was sent to all ECURIE States through the ECURIE network in order to provide all States access to long-range atmospheric dispersion results.