2024 年 23 巻 3 号 p. 81-100
In this study, the perceptions of Tokyo Electric Power Company employees and executives concerning tsunami risk at the Fukushima Daiichi Nuclear Power Station during the years 2008 to 2009, predating the 2011 accident at the facility, are investigated. Newly available court records and other investigative materials are utilized. The findings of this study reveal significant disparities in the perceptions of individuals within the TEPCO organization during the period of interest regarding the risk of tsunami hazards in Fukushima. The perception of tsunami risk and the level of support for long-term evaluation by a government panel, which indicated a high likelihood of a tsunami earthquake near the Japan Trench off the Fukushima coast, exhibited an inverse relationship with one's position within the corporate hierarchy. The employee who held the lowest position in the company was the most concerned about the risk, while those in higher positions were less concerned. This trend can be comprehensively explained by the theory of cognitive dissonance and various biases including affiliation bias, status quo bias, and non-expertise avoidance bias.