Perspectives on LWR severe accidents and public risks

Abstract

Risks of light water reactors (LWRs) for the public were recognized as an important issue and are subject of several probabilistic risk assessments (PRAs), starting with the WASH-1400 risk study performed in early 1970s (US Nuclear Regulatory Commission, 1975). Nuclear safety goals were also formulated based on these studies and/or independently. Both the goals and the formulation of the risks considered the effects of radioactivity releases on the health of a population affected in the vicinity of a nuclear power plant undergoing an accident. WASH-1400 also considered the land contamination that a radioactive release may inflict.The Fukushima accident has highlighted that the principal consequences of a nuclear severe accident may not be the immediate fatalities and injuries and the latent (cancer) health effects, but the societal upheaval and the economic damage that could be caused by a major release of radioactivity to the environment. Such consequences of a severe nuclear accident bring a quite different focus to the risk profile of large-scale deployment of nuclear power in the world. This is addressed in this paper, along with the ancillary issues; design basis, residual risk, cost benefit and back-fit rules, GEN II plants, GEN III + plants, operator performance during severe accidents, fear of radioactivity, and finally public confidence in nuclear power. The paper addresses the above-listed topics, primarily with personal perspectives which may not be shared by the nuclear industry and/or the nuclear regulatory establishments, partly or in whole.