On Feb. 23, 2005, Kobe University professor Katsuhiko Ishibashi appeared before the Lower House Budget Committee and pointed out the risks of operating nuclear power plants in earthquake-prone Japan.

"An earthquake and its seismic thrust can hit multiple parts (of a nuclear plant)" and induce not one but a variety of breakdowns, Ishibashi, an expert on Earth and planetary sciences, told the lawmakers.

Such a scenario could knock out even the backup safety system and possibly result in a "severe accident," such as overheating of the reactor core or even a runaway nuclear reaction, he warned.