Power restored, ‘cold shutdown’ at two Fukushima reactors
21 Mar 2011
Tokyo: Utility Tokyo Electric Power Co (TEPCO) extended external power cables to the No 2 and No 5 reactors at the Fukushima nuclear park on Sunday, allowing it to restore systems to monitor radiation and other data, light the control room and cool down the reactors and their spent-fuel storage pools at these reactors.
The No 5 and 6 reactors also stopped safely Sunday with the temperature of the water inside falling below 100 C, achieving so-called ''cold shutdown.''
TEPCO is now moving ahead with work to lay power cables to the two remaining reactors still without electricity after fire trucks sprayed water earlier on Monday to help cool fuel pools.
Though external power lines have been attached to Unit no 2 it may take a few more days before the vital cooling system is restored.
The containment vessel of the reactor suffered damage in its pressure-suppression chamber, and some parts replacements are needed in the electrical system, according to the government's Nuclear and Industrial Safety Agency.
Earlier Monday, fire trucks sprayed water at the No 4 reactor's spent-fuel pool for the second day running, even as water was poured into the No 3 unit. So far 3,700 tons of water has been poured into Unit no 3 in a bid to lower the temperature in its fuel tank.