Japan's prime minister said today that the country's tsunami-damaged nuclear plant has achieved a stable state of "cold shutdown," a crucial step toward the eventual lifting of evacuation orders and closing of the plant. Prime Minister Yoshihiko Noda's announcement was intended to reassure the nation that significant progress has been made in the nine months since the March 11 tsunami damaged the Fukushima Dai-ichi facility.
"The reactors at the Fukushima Dai-ichi nuclear power plant have reached a state of cold shutdown," Noda said. "Now that we have achieved stability in the reactors, a major concern for the nation has been resolved." A cold shutdown normally means a nuclear reactor's coolant system is at atmospheric pressure and its reactor core is at a temperature below 212 degrees Fahrenheit, making it impossible for a chain reaction to take place. Still, experts say the plant 140 miles northeast of Tokyo remains vulnerable to problems and closing the plant safely will take 30 or more years. (More Japan stories.)