World Notes

The No. 2 reactor at Kansai Electric Power Co.'s Mihama nuclear power plant, located 220 miles west of Tokyo, was operating at full capacity when an alarm sounded. Radiation levels in one steam generator soared to 1,250 times the normal level, triggering the emergency cooling system. Within seconds, tons of cold water began pouring in, averting a meltdown of the reactor core. But company officials acknowledged that malfunctioning safety valves had allowed a "small amount" of radiation to escape.

Containing the political fallout from Japan's worst nuclear accident may prove more difficult. The mishap at the 19-year-old facility underscored growing fears around the globe about the mechanical wear and tear that occurs - inside nuclear plants as they age. Such concerns could hobble the government in its drive to double the number of nuclear reactors to 80 during the next 20 years, in order to reduce Japan's dependence on imported fossil fuels.