International Exchange of Radiological Information in the Event of a Nuclear Accident - Future Perspectives

Transcription

1 BY International Exchange of Radiological Information in the Event of a Nuclear Accident - Future Perspectives Marc DE CORT Environment Institute, CEC JRC-Ispra, Italy Hermann LEEB Bundesamt fur Strahlenschutz, Institut fur Strahlenhygiene, Oberschleissheim, Germany Gerhard DE VRLES, Lothar BREITENBACH Environment Institute, CEC JRC-Ispra, Italy Wolfgang WEISS Bundesamt fur Strahlenschutz, Institut fur Atmospharische Radioaktivitat Freiburg, Germany Abstract. Immediately after the Chernobyl accident most European countries established or enhanced their national radioactivity monitoring and information systems. The large transboundary effect of the radioactive release also triggered the need for bilateral and international agreements on the exchange of radiological information in case of a nuclear accident. Based on the experiences gained from existing bi- and multilateral data exchange the Commission of the European Communities has made provision for and is developing technical systems to exchange information of common interest. Firstly the existing national systems and systems based on bilateral agreements are summarized. The objectives and technical realizations of the EC international information exchange systems ECURIE and EURDEP, are described. The experiences gained over the past few years and the concepts for the future, in which centra) and eastern European countries will be included, are discussed. The benefits that would result from improving the international exchange of radiological information in the event of a future nuclear accident are further being described.. Existing National and Bilateral Systems After the Chernobyl accident monitoring networks and information systems of various kind have been established in many European countries. Furthermore there was the necessity to get quick information about the situation beyond national borders. Therefore within the framework of bilateral agreements between various European countries provision has been -59 -

2 made and technical systems have been established to exchange data and information of mutual interest. In the following the situation in Europe is summarized [,2, 3, 6]... Objectives of the Assessment and Exchange of Radiological Data and Information There are different objectives for the installation and permanent operation of technical systems for environmental monitoring and information exchange. The major objectives are: - to monitor the normal radiological situation of the environment and to determine the permanent background levels; - to provide early warning to competent authorities in cases of abnormal changes of the normal situation; - to assess the dose and the risk to man, which might be caused by a radioactive contamination of the environment; - to assure harmonized actions across national boundaries; - to proof, that the accepted secondary intervention levels for food and feeding stuffs are enforced within the member states of the European Union; - to inform national and international parliaments in due time; - to inform the public fast and in an objective way; - to improve the reliability of diagnostic and prognostic transport models. Three different types of cross-boundary exchange of radiological data and information between European countries can be distinguished, e.g., the exchange between - the local authorities on both sides of a national boundary; - two or several countries at governmental level; - two or several nations and multi- or supra-national organisations. The objectives of the three types are different and so are the requirements for the exchange of data and information..2. General Aspects for the Data Collection, -processing, and -exchange There seems to be agreement that six different types of radiological data are required for the assessment of contamination of the environment, the dose to the population, and decision making, e.g., the - gamma doserate; - activity concentration of the air; - deposition of radionuclides on the ground; - specific activity of foodstuff; - specific activity of feeding stuff; - dose contributions via the relevant pathways. Regional and national data centers are available in many European countries. Some of these centers have made provision or are planning to exchange radiological data and information as described in this paper. In the following chapters some of these systems are briefly described

3 .3. Present Status of the European Monitoring and Information Systems The objectives defined above can be met in many ways. The existing monitoring systems in 3 European countries (Table ) clearly show this by applying various strategies and technical systems. Automatic monitoring systems at fixed ground-based stations are combined with mobile units for in-situ measurement and with stationary and/or mobile units for sample collection and subsequent measurement in remote radiological laboratories. Automatic monitoring networks play an important role in many national concepts for the surveillance of the radiological situation in the environment. Many of the networks operated in Europe, however, do not have technical facilities for real time in-situ measurements and on-line data transfer to a central computer facility. The areal density of the existing networks varies between 0 and 600 stations per 00,000 km 2 for gamma dose-rate and between < and stations per 00,000 km 2 for aerosols. If we look at the present situation in Europe (Fig. ) there seems to be no systematic difference between the systems in countries with and without nuclear power production. Other criteria such as the total population or the population density do not play a significant role for the design of the networks either. Four types of networks can be distinguished: - manual collection of data without using a computer; - manual collection of data, evaluation of data in a central computer; - online computer-controlled monitoring networks, where data are collected by and evaluated in a central computer; - on-line monitoring and information systems which do not only collect and evaluate data but also support all competent authorities. Most systems are used for internal tasks of the authorities, some are also designed to inform the public. Most European systems are computer-controlled monitoring networks..4. Examples of Existing Systems In the majority of the European countries on-line monitoring of gamma dose-rate with data transmission to a central computer is performed. Examples of existing national systems are: The French TELERAY system collects data of more than 65 gamma dose-rate probes and transmits them to a central data processing unit. In normal operation mode, every probe is called from the center once a day. The probes are able to transmit an alarm if predefined threshold-values are exceeded. The public is informed about the radiological situation via videotext (minitel) []. The British RIMNET (Radioactive Incident Monitoring NETwotk) system is a complete national nuclear emergency response system. Its functions include storage, analysis, vizualisation and communication of large volumes of numerical and textual data around the UK []. The German IMIS (Integrated Monitoring and Information System) [9] consists of three operational levels: - collection of radiological data from state-of-the-art monitoring networks and measurement laboratories; - presentation of measurements including transport and dose assessment models; - evaluation of data, management of the consequences of a given situation, legal enforcement of protective measures and information of the public. -6 -

4 Euromap a IRR-BfS /3/20 :3.:O.:995; Euromap lar-bfs Tl/3/20 (.0.995) Figure : Overview of gamma dose-rate and aerosol monitoring networks in Europe (Because of ignorance of the correct position of its stations, the French aerosol monitoring network is indicated by a symbolic point) -62 -

5 Table : Overview of the European monitoring networks (September 995). Planned monitoring stations or early warning systems are indicated in brackets. Country Austria Belgium Bulgaria Croatia Czech Rep. Denmark Estonia Finland France Germany Greece Hungary Ireland Iceland Italy Latvia Lithuania Luxemburg Netherlands Norway Poland Portugal Romania Russia Slovak Rep. Slovenia Spain Sweden Switzerland UK Ukraine Area (ton*) , Pop. ( 000) S S NPP gamma dose-rate (45) ,200 50(+20) 2(+) Air. AerosoV Nuclfde spec. / /3 53/ Iodine 25 Water 40 Eari Warning gamma dose-rate (x) Air (x) (x) Examples of bilateral agreements at governmental level are: Between Germany and France, Russia, and the Czech and the Slovak Republic bilateral agreements define the minimum requirements for a regular exchange of monitoring data obtained at a national level. Since 992 for example daily averages of the gamma doserate obtained at representative stations of the nation-wide German IMIS system in major cities and of the German KFU systems in the vicinity of the NPP Cattenom and Fessenheim are provided once a day by fax to the French authorities [5]. The data are published daily together with the results of the French monitoring system in the widespread Minitel system. The problem of intercomparability of the data is solved by the continuous operation of a French (and a Swiss) gamma detector in the vicinity of a gamma detector of the German network near Freiburg. In an emergency situation the data exchange on a 2 hourly basis is aimed for. For this purpose a computer-based system for the automatic data exchange is currently being developed. It is expected to become operational by the end of 995. There are similar activities in the Nordic countries Denmark, Finland, Iceland, Norway and Sweden which aim for the harmonization of the data exchange between these coun

6 tries. The system includes gamma dose-rates from the fixed monitoring networks that exist. An alternative way is used for the exchange of processed data and information between Germany, Russia, the Czech and the Slovak Republic. Rather than exchanging monitoring data, documents are exchanged, which may consist of processed data such as maps with monitoring data, time series of data at particular sites, and free text messages. Routine exchange of documents of this kind has been started with the Russian Federation in January 994. On a weekly basis documents with dose-rate data from the German IMIS and the corresponding IRIS (Integrated Radioactivity Information System) at the NPPs Smolensk and Novoworonesh are exchanged. 2. The EC International Information Exchange Systems 2.. Introduction Immediately after the accident at Chernobyl NPP, both the International Atomic Energy Agency (IAEA) and the Commission of the European Communities (CEC) set up a system to meet the requirements for early warning and exchange of information. The IAEA system was established under the Early Notification Convention [0] (2 October 96) and the Early Assistance Convention [] (26 February 9). The basis of the CEC system is the Council Decision of 4 December 9 [2], which resulted in the European Community Urgent Radiological Information Exchange (ECURIE). By this system the EU Member States can exchange and submit to the Commission the information required by the Council Decision. Since the majority of the aims and needs for both systems overlap, it was decided between the IAEA and the CEC to harmonize as much as possible both systems, which resulted in the establishment of a common code (CIStructure) and coding/decoding software (CDS). The current ECURIE system however is not tailored to the exchange of real-time monitoring data. Integration of national data exchange at a European level would speed up the availability of monitoring data at a large scale, essential for model calculations in view of accurate and timely predictions and indispensable to give actual and fast overviews of the contamination levels. The JRC detected these needs and - considering itself in the correct position for doing so having the necessary competences and taking part in the support activities REM (Radioactivity Environmental Monitoring) and ECURIE for CEC DG I.C.l, Radioprotection, Luxembourg - decided to organize a workshop to investigate the technical aspects that would be needed for the creation of such a European-wide radiological information exchange system (EURDEP) The ECURIE System 2.2. General Description of the Current System The ECURIE system consists of a telex based communication network between the CEC and the Member States, through which radiological information can be exchanged. At present, all ECURIE telex messages pass through the Commission Telex Centre, Brussels (See Figure 2). To receive priority treatment the messages are included in a IATA telex code, which allows for automatic recognition of ECURIE messages. The structure used for -64 -

7 exchanging information is the Convention Information Structure (latest version of 6 June 99) [3]. In order to avoid language translation problems it was developed as a short code of specific meaning. Each type of message that might be transmitted is represented as a block of code. Within each block the parts of a message are labeled as line numbers. The C.I.Structure does not only provide information on radiological measurements, but also on predicted values, site meteorological data and taken decisions (countermeasures). Coding-decoding software (CDS) has been developed to reduce the time needed to code and decode the messages and to improve the reliability. The part of the software for decoding messages was written by the IAEA whereas the encoding program was developed at JRC-Ispra. The encoding software is a menu driven program that helps the user to produce a valid C.I.Structure code, mostly by means of selection tables, and performs a validity check on the type of input. Additional help on line for every line number is available. In the present version of the CDS a hardcopy of the encoded message can be made to copy the message on a telex or the message can be sent away via an automatic telex device. Decoding software translates the encoded C.I.Structure message into a plain text message. Figure 2: ECURIE message flow [5] ECURIE provides four exercise levels with which the various aspects (communication, contact of responsible persons, exchange of data) are tested [4]. In Figure 2 the flow of a typical ECURIE message is shown: a notification message is generated by CEC DG I/C/ Radioprotection, Luxembourg ( ), sent by internal electronic mail to the Commission Telex Centre (CTC) (@), converted to the telex network ( ) and transmitted to the Member State contact points ( ). The Member States answer by sending an appropriate response message via CTC ( ) to DG FC/ ( ). In case of a level 3 exercise, this is followed by the transfer of two encoded messages containing data from each MS contact point to the CEC, who forwards it again to each contact point Experiences gained Over the past three years, five exercises of level 3 have been held. Despite that in most cases the majority of the exercise objectives were met (transmission of the messages, contact of national radiological duty officers, coding and decoding of messages), important -65 -

8 inconveniences were detected []: - the present communication system (telex) is too slow. Also the communication link between telex and the EC internal electronic mailing system (Figure 2: between and ) appeared to be not reliable enough for emergency situations; - the joint development of the CDS by the IAEA and the JRC has lead to inconsistencies between the coding and decoding modules and a too high memory demand. 2,2.3. Future Developments Because of above mentioned deficiencies the following three actions are foreseen []: improvement of the CDS software. The new CDS, called CoDecS, will be running under Windows 3., using a programming language that allows migration to a native version under Windows 95. The following requirements were defined: - automatic decoding/encoding of messages; - assistance when compiling the messages; - assistance in generating summary reports; - unattended and automatic daily exercises; - alarm signaling; - multi-language user interface; - automatic forwarding of messages. telex communications will remain available as backup but to improve respectively the integrity of the messages and the transmission speed, the.400 protocol over Euro- ISDN will be used as default for the transmissions. creation of an on-line ECURIE database with WWW (World Wide Web) access The European Union Radioactivity Data Exchange Platform (EURDEP) System General Description and Objectives Resulting from the EC workshop on the 'Technical aspects of International Exchange of Radiological on-line monitoring data' (-3 June 994, Arona, Italy), agreements about the realization of a pilot project were reached. This project should include the following tasks: investigate the feasibility of using for the exchange of radiological data; setup a regular exchange of data between some European countries; use the information about the national monitoring networks submitted by the countries to define which radiological data could be exchanged now and in the future; define a common data-format for the exchange of the data and write software to convert the national format into the common format; establish a 'European network', based on existing monitoring stations on a 00 x 00 km grid Data Exchange Format The various data items were based on the information available from the existing national formats, and are arranged in five main sections; geographical information about the sampling location, measurement information (primarily on gamma dose-rate and airborne con

9 centration, but with the possibility to include additional sample types), additional sample characteristics, meteorological information at the sampling location and information about the sender. The key-elements that influenced the data-exchange format (more detailed information can be found elsewhere [6,]) are threefold: flexibility: the EURDEP data format has been defined such that it allows to include future radiological data as it becomes available. The structure of the format itself allows flexibility in the order of the data and the possibility to define static information only once as global data to reduce the size of the data; compatibility: the format was designed that it can be read and produced by software running on different platforms; robustness of the format: errors generated during the transmission should be detected and wrapping lines or adding headers or footers by software should have no impact on the successful interpretation conversion Experience gained from the Pilot Project From the beginning of 995 onwards consecutive participating institutes are being contacted by the JRC and invited to send their radiological information. These data were merged together at the JRC-Ispra and returned to the participating institutes. Until now (October 995) successful bi-directional exchange of test-messages are regularly done with Germany, United Kingdom, Austria, Denmark, Norway, Sweden, Finland and Ireland. All communications are performed through SMTP (Simple Mail Transfer Protocol), except for Table 2: Summary statistics of EURDEP exercise transmission delays (in hh:mm) ramm 503/0«asmm mmm mmm. mmm imm:m mmm HOMKffi: mmm vomea :6-0:03<'> 0:5 3:00 2:06 0:55 0:03 0:50 :05-0:03 () :03 3:04 :4 2:05 0:04-0:0 0) 0:4 4:2 0:0-0:03 W 0:3 0:49 :02 0:0-0:0«> 3:40 0:0 issiflii lillfii 0:0 0:0 2:02 :26 2:04 :20 9-0:0 () 0:52 5:0 0:0 3:22 2:0 :2-0:2"' -0:0 () 0:0 0:50 0:22 islfp 0:04 :03 0:3-0:03 () 0:3 0:5 2:52 3:22 :40 0:22 0:0-0:06 () 0:20 2:5 0:4 0:50-0:03") -0:03<" 0:0 2:02 :26 :02 0:0-0:2 ( " -0:0 (> 0:50 wmm :6 :05-0:03 () :03 0:49 3:22 :4 2:05 :20 2:00-0:0<" 0:52 5:0 <2) 0:0 0:22 2/2 3/3 3/3 5/5 6/6 6/6 / 6/ 5/ 6/ 6/ 5/ 6/ 6/ / / / imiiill 0:45-0:03 ( " 3:00 2/ :23-0:03 () :4 6/ 0:32-0:03 () 3:40 5/6 :0-0:0 () 5:0 2/4 4/4 0:40-0:2 () 3:22 3/3 / 3/5 '" Negative delays are caused by inaccurate clocks, (the JRC mail server is often up to 5 minutes behind) '" The JRC IP-Server was down for about an hour. -6 -

10 the UK where.400 is used. The following experiences were gained: establishing a first contact using.400 can several months due to the involvement of the different PTT's; the store and forward nature of makes that the delay in delivering mail varies largely. We also experienced several cases in which messages disappeared; mailboxes are not always frequently read and not checked by other persons in case of absence. Many communications sent to the contact points were reacted on very late; the maximum delays (see Table 2) of the transmissions clearly show that public cannot be used to exchange radiological data in case of an alert. Table 2 lists the average, minimum and maximum travelling time and the number (NP) of messages by participant. The first information was not received from all contact points, because incompatible with the automated manner in which some send their data. It must also be said that the accuracy of the traveling time is in the order of several minutes due to the differences in clocks on the various computers, gateways and wrist watches! Future Perspectives and Developments Begin 996 the development of an interface between the decision support system RODOS and EURDEP is planned. A second workshop is foreseen for June '96 to discuss the results of the pilot project: the experiences gained will induce discussions on several modifications: has the advantage that it does not give security problems, but using it on top of Internet may not be reliable enough for the purposes of EURDEP. Two alternatives that will be proposed for a more reliable connection are the usage of.400 and a protocol developed at the AR Institute of the German BfS, both on top of ISDN; review of the data format and porting of it to the EDIFACT (ISO 935) standard. a more dense geographical coverage of the network than the initial 00 by 00 km; participation of central and eastern European countries; installation of the conversion programmes at the contact points; obtain an official status for the project. 3. Conclusions The Chernobyl accident has triggered the development of regional on-line monitoring networks as well as the improvement of rapid national and international data transfer. However, the existing situation must be characterized as highly inhomogeneous. No accepted standards for data collection and information exchange are available yet. The national technical solutions differ in radiological as well as in data processing aspects. The data exchange systems on bilateral basis are also special solutions for the intended purpose. On the other hand there is also the fast development of long range transport models and real-time decision support systems that require rapid access to international monitoring data in order to allow for accurate and timely predictions on a European scale. Therefore the development of EURDEP is necessary to bring together the essential elements for a Euro- -6 -

11 pean-wide emergency response system. The long term objectives of EURDEP are therefore: ensure the comparability of measured data; get an overview about the radiological situation in the whole of Europe; provide the CEC with all necessary data; provide national authorities with information from other European countries; interface with an on-line decision support system [4]. References [I] W. Weiss, Exchange of Radiological Data and Information between European Countries, NEA- Workshop 'Emergency Data Management", Zurich, 995 [2] W. Weiss, Systeme zur Uberwachung der radiologischen Lage- gegenwsrtiger Stand im internationalen Vergleich; Ansatze zur Harmonisierung, FS-94-4-I, Stand des Notfallschutzes in Deutschland und der Schweiz, ISSN ,20-25,994 [3] S. Vadfi, Die EuropSische Union und der Strahlenschutz der Bevolkerung bei einer radiologischen Notstandssituation, FS-94-4-I, Stand des Notfallschutzes in Deutschland und der Schweiz, ISSN ,35-390, 994 [4] J. Ehrhardt, J. Paesler-Sauer, O. Schuele, G. Benz, M. Raffat and J. Richter, Development of RODOS, a Comprehensive Decision Support System for Nuclear Emergencies in European Overview, Radiation Protection Dosimetry, Vol. 50, Nos 2-4, pp (993) [5] J. Narrog and R. Obrecht, Transboundary Data Management for Plants near National Borders, NEA- Workshop 'Emergency Data Management", Zurich, 995 [6] W. Weiss, H. Leeb, F. Eberbach, Basic concepts and Objectives of Technical Systems for Computerbased National and International Exchange of Data and Information, EU workshop on the Technical Aspects of International Exchange of Radiological on-line Data, Ispra, June 994 [] G. Linden, "Teleray-Minitel, the French National Network for the Radiological Survey of the Territory", NEA-Workshop 'Emergency Data Management", Zurich, 995 [] R. Jackson, "Treatment and Handling of Radiological Data for Nuclear Emergency Response: The United Kingdom RIMNET Arrangements", NEA-Workshop 'Emergency Data Management", Zurich, 995 [9] W. Weiss, H. Leeb, "IMIS - The German Integrated Radioactivity information and decision support System", Radiation Protection Dosimetry, Vol. 50,993 [0] IAEA - Convention on early notification of a nuclear accident, 2 October 96, Vienna, Austria. II] IAEA - Convention on assistance in the case of a nuclear accident or radiological emergency, 26 February 9, Vienna, Austria. [2] Council Decision of 4 December 9 on Community arrangements for the early exchange of information in the event of a radiological emergency, OJ No L 3/ [3] CEC - Convention notification and information structure, DOC No 609//9 EN, 6 June 99. [4] CEC - ECURIE level-3 exercise, 99 - Position following the Meeting of the exercises Working Group 26-2 February, 99, and its subsequent evolution. DOC No 600//9 EN. [5] M. De Cort, 'Regional Monitoring Networks and International Data Exchange', 'Environmental Monitoring, Off-site Emergency Response to Nuclear Accidents: Textbook based on training courses organized at SCK/CEN Mol, Belgium (in preparation) [6] G. de Vries, M. De Cort, S. Giuliano and S. Gatti, Technical Note: 'Concept and development of an exchange format for European Radioactivity data' (in preparation) [] M. De Cort, L. Breitenbach and G. de Vries, The on-line European Community Urgent Radiological Information Exchange (ECURIE) information system, NEA-Workshop 'Emergency Data Management", Zurich, 995 [] M. De Cort and G. de Vries, The EU Radiological Data Exchange Platform (EURDEP): recent developments, NEA-Workshop "Emergency Data Management", Zurich,