Fukushima's emergency power failure traced to U.S. design
http://www.asahi.com/english/TKY201106160177.htmlThe accident at the Fukushima No. 1 nuclear power plant following the Great East Japan Earthquake and tsunami of March 11 quickly worsened and spun out of control because the U.S.-styled design for its emergency power sources had been adopted without modification 40 years ago--a source at Tokyo Electric Power Co., the plant operator, told The Asahi Shimbun.
In the U.S. design, emergency power generators are installed underground to guard against tornadoes and hurricanes. The Fukushima plant was, however, swamped when the tsunami rose more than 10 meters above the normal sea level along the coast and knocked out its power supply in the blink of an eye.
In the U.S. nightmarish scenario, used in the 1960s to draw up protection measures against nuclear plant disasters, violent winds, as strong as 360 kph, strike the plant. A giant tree growing nearby, uprooted and airborne, crashes through the walls of a reactor building like a missile and destroys the emergency power sources. The emergency power generator is located in a turbine building, which has thinner walls than the reactor building next door. Thus, it was deemed safer to install the emergency power generator underground to protect it from a "tree missile," explained the TEPCO source.
"We built them the way they told us to build them, because they said they wouldn't guarantee safety unless we built them according to the U.S. specifications," recalled a former senior official at the former Ministry of International Trade and Industry.