Nine years earlier, Yoshihiro Kinugasa, the leading seismologist on Japan's nuclear licensing panel, signed off on a pre-construction study of the site. The report identified three fault lines, each less than 10 kilometers (6.2 miles) long, or just under the length regulators deemed threatening.
In 2005, Kinugasa switched roles and published a study with Hokuriku Electric engineers that rebutted neighbors' claims the plant was unsafe. After the quake, government scientists found the fissures were in fact a single fault of 18 kilometers that could produce more shaking than the plant was built to withstand.
A Tokyo Institute of Technology professor, Kinugasa has advised utilities, inspected plant sites and helped rewrite nuclear safety rules. His multiple roles show the conflicts of interest endemic in Japan's nuclear power industry, says Takashi Nakata, a Hiroshima Institute of Technology seismologist.