The GRS Emergency Centre during the Fukushima NPS Accident: Communicating Radiological Information to the Public

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1 The GRS Emergency Centre during the Fukushima NPS Accident: Communicating Radiological Information to the Public F.-N. Sentuc, S. Dokter Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) mbh Schwertnergasse 1, Köln, Germany Abstract: During Fukushima 2011, the GRS Emergency Centre continuously analysed the situation and provided detailed information on the current plant status and the radiological consequences, not only for the German government but also for the worried public. It became clear through media and public enquires that information, even at a very basic level, was needed in the field of nuclear technology and radiation protection. Therefore, technical experts and public relation team members worked together to prepare explanatory and background material. Owing to this strong interest, GRS established a special Fukushima portal on its website, to meet the need for information. As well as the technical aspects, which dominated the expert s work in the GRS Emergency Centre, one challenge was communicating the radiological information to the public in a comprehensible yet professional way. 1 INTRODUCTION The earthquake and subsequent tsunami on March 11 devastated the shoreline and caused the loss of more than ten thousand lives in Honshu, Japan. As a result of the effects Chernobyl had on Europe, there was a strong media focus on what would happen to the nuclear power stations (NPS) in Japan. As Fukushima can be seen as a sequence of events, the reactor cooling system in several blocks in Fukushima Daiichi failed. Finally, this led to a release of radioactive material into the environment, so that the event was then rated with the highest INES (International Nuclear Event Scale) level 7. These emissions and subsequent contaminations had significant radiological consequences, like the overexposure of workers at the plant site and this made the evacuation of many people living in the vicinity of the NPS Daiichi necessary. Also, in Europe, the effects of Fukushima could be observed both directly and indirectly, e.g. through the analysis of slightly enhanced radionuclide concentrations and through the uncertainty of the public. Therefore, GRS activated its Emergency Centre to provide detailed information and analyses for the competent authority as well as for the public. 2 THE GRS EMERGENCY CENTER To support the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety (BMU) in the case of severe nuclear accidents, e.g. at a NPS, GRS has an Emergency Centre (GRS-EC) at its headquarters in Cologne, Germany. The tasks of the GRS-EC are to collect and evaluate relevant data and to assess the plant status, as well as to prepare respective prognoses (e.g. of release and dispersion of radioactive material). In addition to these technical tasks, the GRS-EC is also intended to support the information to the public. To be able to fulfil these tasks, the GRS-EC was and is staffed with a team of experts covering plant behaviour (i.e. engineering, thermohydraulics, core-behaviour etc.) and radiation protection (e.g. regarding dispersion modelling and source-term evaluation for radioactive releases) as well as communication and public relations.

2 On March 11, GRS started a routine analysis of the situation and the emergency potential for the NPS in the affected areas with a small team of 3-4 experts at around 7:30 a.m. Due to the escalation of the plant status in Fukushima Daiichi, the team expanded in the course of the morning and a first assessment of the on-going events at the Fukushima NPS was issued around 12 a.m. (CET) to the BMU. Responding to further information, in particular regarding the loss of off-side and internal power, due to the flooding of emergency dieselgenerators, the GRS-EC started operating officially at 12:30 a.m. From this point on, GRS- EC was in operation until the middle of April (24/7 until March 18, afterwards gradually reducing manpower). During that time, approx. 30 staff members were directly involved. Additional experts from GRS supported the team on a case-by-case basis with regards to specific problems. Of course, it was extremely important to be continuously and quickly informed, thus, e.g. a Japanese translator was involved enabling direct access to the current news and press releases. 3 COMMUNICATION OF RADIOLOGICAL INFORMATION TO THE PUBLIC As in other countries, the accident at the Fukushima Daiichi NPS in March 2011 gained huge amounts of media and public attention in Germany. Starting with the first questions from the news agencies at around 12 a.m. on March 11, GRS was confronted with about 700 media and individual requests for information, resulting for example in more than 30 TV- and radio-interviews in the following weeks. Responding to this intensive need for information, GRS launched a special website and published all status reports prepared by the GRS-EC on this new Fukushima Information Portal. Until October 2011, GRS counted approximately 5 million page views on this new website ( Figure 1: General manager F.-P. Weiß, interviewed by a news channel 3.1 Development of Public and Media Interest and Enquiries While during the first few days, interest focused on the plant s status ( Can core-melting be avoided? ), radiological aspects soon dominated the questions posed by journalists and members of the public, as a consequence of the first venting. Relevant topics, in this regard, ranged from immediate radiological consequences (e.g. releases of radioactive material resulting in the contamination of areas and the need for evacuation) to indirect effects (e.g. potential hazards caused by the possible importing of contaminated foodstuffs from Japan). Apart from information directly related to the concrete accident, requests also showed a general need for explanation of the basic terms, effects and concepts in radiation protection. 3.2 The Need for Providing Basic Knowledge Prior to the Fukushima accident, it was already known that most of the public and media were unfamiliar with the basic quantities and measurement units concerning radioactivity and ionizing radiation. The meaning of units like Becquerel and Sievert had to be explained briefly and comprehensibly. The relation between radioactive decay, energy released and absorbed dose, was of particular interest to journalists. An important aspect was the explanation of the quantity effective dose including further information, notably, the comparison between the doses received by workers in Fukushima and e.g. the doses

3 caused by natural background radiation. This was achieved by many short articles and explanatory figures that were posted on the website. The examples given in Figure 2 indicate doses in the range from some µsv e.g. from natural background radiation (external exposure), dental X-ray, non-stop flight (one-way) from Frankfurt to New York (blue boxes) up to some msv and Sv (dose limits, lethal doses, red boxes). With the focus shifting from the plant status to the radiological situation questions arose regarding the different types of radiation and the matching shielding possibilities. Additionally, the different exposure pathways (internal and external exposure) had to be addressed by the GRS websites (see e.g. Figure 3). The effects of ionizing radiation and potential danger i.e. the possible impact on human health were of particular concern. There was e.g. the perception that an effective dose above 1 msv is a dangerous dose. This was partly caused by the different dose limits (see below) and by reports where units like µsv, msv and Sv were mistakenly used. On the other hand, the impact of specific radionuclides on the environment (e.g. plutonium) were discussed when reports referred to corresponding measurement results. Figure 2: Some mean values for radiation doses (as a measure for the biological effect of ionizing radiation quantified as effective dose in Sievert) resulting from different sources in Germany to illustrate the relation between natural and artificial contributions in daily life. Figure 3: Explanatory illustration (left) and flow-chart (right) for different exposure pathways in general (internal, external) and exposure through atmospheric releases, respectively.

4 3.3 Information on the Current Radiological Situation The provision of background information by the Emergency Centre for the public is part of the GRS mandate as non-profit organization. The expert team primarily informed the competent authority (BMU) about on-going developments in Japan via status reports. The GRS status report sent to the BMU and released in parallel on the website through the internet team offered detailed information on the current status of the different plant sites (Daiichi, Daini etc.), the radiological situation in Japan and the external disaster control measures. The status reports provided technical and radiological information promptly and were updated several times a day at the beginning and towards the end twice a week until July Additionally, these reports were translated into English and published on the website. In the course of the event, approximately 200 reports were issued by the GRS-EC. In addition, specific information regarding the current situation and corresponding enquiries were posted on the Fukushima Information Portal together with the appropriate background material for the public. Information on topical issues and on the current status was released as soon as possible to be up-to-date and in particular, to meet the demand for explanatory material concerning the radiological situation. One challenge for the experts and the internet team was to prepare technical facts and vocabulary not only in a professionally correct manner but also comprehensible for any interested party. However, sometimes even simplified explanations were reduced or taken out of context by the media. In the following text some examples of typical enquiries from the public can be found Exposure of workers and dose limits In the German media, worries about the health of workers at the Fukushima Daiichi site soon came up. In this context, one issue was the problem of communicating different dose limits to the public and the media. To many people, the existence of a 1 msv/a dose limit implies that any dose that significantly exceeds this value must be harmful and that higher dose limits (e.g. 20/50 msv/a or in case of radiation workers at Fukushima Daiichi 250 msv/a) are hardly tolerable and are caused by reasons other than protection. This perception can lead to judgments on real/potential risks in single cases which are not consistent with that of an expert s evaluation (e.g. a worker received a dose of 60 msv, what is the consequence of exceeding a dose limit? ). The discrepancy between an expert s and an ordinary person from the public s view can cause a loss of credibility ( dangers are played down ). To plausibly explain the rationale behind the different dose limits (e.g. for radiation workers and the public) was and is challenging but crucial Venting and release of radioactive material to the atmosphere After the first venting at Fukushima Daiichi, the focus shifted to the radiological consequences of a radioactive material release to the atmosphere on the people in Japan and also in Germany or Europe. In addition to the general background information, the radiation protection experts provided various analyses on the radiological situation in graphical form that were continuously updated. Charts of the local dose rates directly at both Fukushima plant sites were provided and like other figures often used and cited or linked by the media (see Fig. 4). To give a short overview on the radiological situation in the prefectures around the NPS sites, local dose rate data were routinely collected from the Japanese websites and displayed in a figure (see Fig. 5). This figure was created in answer to the coverage of evacuation and other measures of disaster control and emergency response taken by the Japanese authorities. Afterwards, GRS was confronted with many enquiries e.g. like the one from a manager who was concerned about his workers health in a Chinese plant ( Should we evacuate our staff immediately? We have an airplane already available. ). The enquiries showed that these measures taken in Japan provoked fears even in Germany, not only for

5 the Japanese but also for the German people ( Can the affected Japanese go back to their houses some day? or Can the released radionuclides even reach Germany? ). Figure 4: Chart of dose rates measured on-site Fukushima Daiichi (left), with points of measurements located on map (right) Figure 5: Map displaying evacuation areas (left) and the graphic showing the dose rates in five prefectures (right) 3.4 Long-term Effects and Situation Today Shortly after this focus on the direct consequences, long-term effects came into the foreground. One example were the questions that arose after the reports about the contamination of sea water concerning future environmental effects of the releases e.g. for the biota and the import of possibly contaminated seafood or other products from Japan or the contamination of sea vessels. In this case, GRS provided a report about the contamination of sea water and e.g. the consequences on seafood (fish and algae) with a corresponding dose assessment for ingestion.

6 Though the situation in Japan now seems to have stabilised, the plant status and radiological parameters are still observed by members of the Emergency Team. Available data and press releases are collected and scanned for any anomalies. Information on the current situation (tabular overview, TEPCO publications) is still posted on the Fukushima website (see Fig. 6). From time to time GRS is still contacted by the media for information on on-going issues concerning Fukushima and also, on other topics connected to radioactive material and radiation in general. Figure 6: Screenshot of the GRS Fukushima Information Portal 4 CONCLUSIONS During the Fukushima accident, there was a need for prompt and comprehensible information to the public and the media on the current situation. As a result of the lack of basic knowledge of the public, e.g. in the field of radiation protection there was a large uncertainty and consequently, the perception of risks of a layman differs to that of an expert s evaluation. To prepare facts and background information technically correct but comprehensible was a challenge, bringing together technical experts and public relation team members. Though the degree of the public interest was not anticipated at first, the communication between competent authorities, public and the media proved itself in practice. For the future, the importance of providing information to the public should be taken into greater account. Hence, the GRS-EC will improve its capabilities to be better prepared and staffed for this task. TSOs in general are appointed in terms of knowledge and credibility and therefore, can and should play a prominent role in informing the public about nuclear technology and radiation protection. In this field, as well as for the technical aspects the collaboration between the different TSOs should be improved even more e.g. via international networking.