Numerical Modeling Methodology and Techniques for the External Flooding Analysis of Ascó and Vandellós Ii Spanish Nuclear Power Plants, During Stress Tests (PAP014349)

Código

PAP014349

Autores

Maria Teresa Otero Alceda, Juan Sabater Alloza, Agustín Alemán Gonzalez, Juan Felipe Arcila Maldonado, Pablo Caffarena de la Fuente, Thomas Cernocky, Iris Cobas Machado, Andrea Costa, Juan Manuel Expósito Pérez, Cesare Alessandro Mosca

Tema

Urban Floods

Resumo

Considering the accident occurred at Fukushima Daiichi Nuclear Power Plant in Japan, the European Council of March 24-25, 2011 stated that ?the safety of all EU nuclear plants should be reviewed, on the basis of a comprehensive and transparent risk assessment (?stress tests?)?. In this context, the WENRA (Western European Nuclear Regulators Association) established the technical contents of the stress tests and how they should be applied to all nuclear facilities across Europe. One aspect of the stress tests is related to External Events. This includes fluvial flood risk or severe local precipitation on the plant site. The purpose of this article is to describe the methodology used by ANAV, the operator of Ascó and Vandellòs II NPPs, for assessing and improving the safety threshold of its plants beyond their design basis, in order to comply with WENRA stress tests specifications concerning External Flooding Events. The analysis begins with the identification of the local environmental factors that can cause a plant flood and all their combinations. Subsequently, the article describes the numerical modeling techniques and the main hypotheses used to represent the consequences caused by a Local Probable Maximum Precipitation (PMP) to Structures, Systems and Components of the Nuclear Plant. The results of the analysis have led to adopting additional measures to increment the Hydraulic Risk safety threshold for the two Spanish Nuclear sites in Catalonia.