Claudia Landman

Kernkraftwerke in Deutschland

Von den 436 KKWs, die im Marz 2011 weltweit betrieben wurden, befanden sich 17 KKWs in der BRD (Nuclear News, A publication of the American Nuclear Society, 2011). Dies waren seit Anfang der 1990er Jahre ausschlieslich DWRs und SWRs. Sie wurden in leicht unterschiedlichen technischen Ausfuhrungen gebaut und unterscheiden sich leicht in Leistungsgrose, Aufbau und Dimensionierung der Kuhlsysteme sowie ihrem auseren Sicherheitsbehalter (Containment). Acht dieser deutschen LWRs wurden nach dem Fukushima-Unfall in Japan im Marz 2011 abgeschaltet (Dreizehntes Gesetz zur Anderung des Atomgesetzes, 2011).

Sequential multi-nuclide emission rate estimation method based on gamma dose rate measurement for nuclear emergency management

In case of a nuclear accident, the source term is typically not known but extremely important for the assessment of the consequences to the affected population. Therefore the assessment of the potential source term is of uppermost importance for emergency response. A fully sequential method, derived from a regularized weighted least square problem, is proposed to reconstruct the emission and composition of a multiple-nuclide release using gamma dose rate measurement. The a priori nuclide ratios are incorporated into the background error covariance (BEC) matrix, which is dynamically augmented and sequentially updated. The negative estimations in the mathematical algorithm are suppressed by utilizing artificial zero-observations (with large uncertainties) to simultaneously update the state vector and BEC. The method is evaluated by twin experiments based on the JRodos system. The results indicate that the new method successfully reconstructs the emission and its uncertainties. Accurate a priori ratio accelerates the analysis process, which obtains satisfactory results with only limited number of measurements, otherwise it needs more measurements to generate reasonable estimations. The suppression of negative estimation effectively improves the performance, especially for the situation with poor a priori information, where it is more prone to the generation of negative values.

STATUS OF THE RODOS SYSTEM FOR OFF-SITE EMERGENCY MANAGEMENT AFTER NUCLEAR AND RADIOLOGICAL ACCIDENTS

Under the auspices of its Euratom Research Framework Programmes, the European Commission (EC) has supported the development of the comprehensive decision support system RODOS (Real-time On-line DecisiOn Support) for off-site emergency management after nuclear accidents for more than a decade. Many national research programmes, research institutes and industrial collaborators contributed to the project, in particular the German Ministry of Environment, Nature Conservation and Reactor Safety (BMU). The RODOS system can be applied to accidental releases into the atmosphere and various aquatic environments within and across Europe. It provides coherent support before, during and after such a release to assist the analysis of the situation and decision making about short and long-term countermeasures for mitigating the consequences with respect to health, the environment, and the economy. Appropriate interfaces exist with local and national radiological monitoring data systems, meteorological measurements and forecasts, and for the adaptation to local, regional and national conditions in Europe. Within the European Integrated Project EURANOS of the 6 th Framework Programme, the RODOS system is being enhanced, among others, for radiological emergencies such as dirty bombs attacks, transport accidents and satellite crashes by extensions of the nuclide list, the source term characteristics and the atmospheric dispersion model.

The Decision Support System RODOS

The chapter begins with an outline of the historical development from the first UNIX-based RODOS system until the most recent Java-based version JRodos. This is followed by an overview of the models contained in RODOS, and a description of the RODOS Center in Germany, where RODOS operates since 2005 at a central location for use by the federal government and the federal states.

Relevant Radiological Phenomena, Fundamentals of Radiological Emergency Management, Modeling of Radiological Situation

The chapter summarizes relevant radiological phenomena, the fundamentals of radiological emergency management, and the modeling of the radiological situation in computer programs. Topics as the data requirements of the models and the actual availability of data in the different phases of an accident and the respective uncertainties are also addressed. The chapter is mainly intended for readers without deeper familiarity with the respective scientific field.

Recent Developments in Nuclear and Radiological Emergency Management in Europe

The chapter outlines the Developments in Nuclear and Radiological Emergency Management from the 4th to the present 7th European Framework Program of the European Union.

RODOS and the Fukushima Accident

The chapter describes the contribution of the JRodos Accident Consequence Group of the Institute of Nuclear Technology and Energy Technology (IKET) as part of the activities of the Karlsruhe Institute of Technology (KIT), Germany, in frame of the Fukushima reactor accident.

Neuere Entwicklungen im radiologischen Notfall-Management im Europäischen Rahmen

Zwischen 1994 und 2002 gab es im Rahmen des 4. und 5. Forschungsrahmenprogramms der Europaischen Union betrachtliche Fortschritte bei der Entwicklung von neuen Methoden und Informationstechnologie (IT) – Werkzeugen fur das nukleare radiologische Notfall-Management, die am Ende der Forschungsperiode allerdings teilweise noch nicht voll einsatzfahigfahig oder schwierig zu verbreiten waren.

Sicherheitskonzept von Leichtwasserreaktoren

Ziel der Reaktorsicherheit ist der Schutz des Personals in Reaktoren und Anlagen des Brennstoffkreislaufs, sowie der Schutz der Umgebung dieser Anlagen und der Bevolkerung. Dazu sollen Storungen, die zur Radioaktivitatsfreisetzung fuhren, durch die Konstruktion der Anlage weitestgehend ausgeschlossen oder – falls Storungen eintreten – deren Folgen begrenzt werden.

Einige reaktorphysikalische Grundlagen

Vor der Beschreibung der jeweiligen Reaktortypen werden einige reaktorphysikalische Grundlagen erklart, die zum Verstandnis der sicherheitstechnischen Konzepte in DWRs und SWRs in den nachstehenden Kapiteln erforderlich sind. Fur ein tieferes Verstandnis muss auf einige reaktorphysikalische Lehrbucher verwiesen werden (Theorie der kernreaktoren, Bd. 1: Der stationare Reaktor, Bibliographisches Institut2.1, 1982; Kernreaktortheorie, eine Einfuhrung, 1961; Introductory nuclear reactor statics, American nuclear society, LaGrange Park, 1983; Introduction to nuclear reactor theory, 2nd (ed), 1983).