The crippled Fukushima Dai-ichi nuclear power plant in Okumamachi, Fukushima prefecture, northern Japan is seen in this March 24, 2011 aerial photo taken by small unmanned drone and released by AIR PHOTO SERVICE. UPI/Air Photo Service Co. Ltd. | License Photo
TOKYO, May 17 (UPI) -- Japan's damaged nuclear power plant lost cooling capacity in the devastating March 11 earthquake before the arrival of the resulting tsunami, officials said.
Operating records of plant operator Tokyo Electric Power Co. released Tuesday revealed the primary emergency backup cooling system of the No. 1 reactor at the Fukushima-Daiichi nuclear power plant failed almost immediately in the magnitude-9 earthquake, NewScientist.com reported Tuesday.
"An emergency condenser system at the Number 1 reactor functioned for less than 10 minutes after the earthquake. The failure lasted for three hours," the records said.
A chronology of events laid out in the records shows the pure chaos experienced in the aftermath of the March 11 quake and tsunami as the nuclear disaster unfolded, the Mainichi Daily News reported.
Just after the magnitude-9 earthquake struck at 2:46 p.m., reactors No. 1-3 began emergency shutdown procedures.
Overheating due to the failure in the cooling system even before the arrival of the tsunami may have accelerated the reactor's meltdown, officials said.
All power to the plant was cut off when a tsunami struck some 45 minutes after the earthquake.
Power source trucks to supply the plant's reactors got stuck in traffic and could not get to Fukushima from nearby TEPCO facilities.
Inside the plant, workers tried to vent the No. 1 reactor to relieve pressure building in the reactor vessel but had to stop about 9:30 p.m.
"We've given up venting operations (to lower reactor pressure). The radiation level is just too high," a TEPCO employee reported.
The documents released by TEPCO do not include any record of the utility's communications with the prime minister's office.
A government committee set up to analyze the causes of the nuclear crisis and the actions taken by both the government and TEPCO to contain it will study the documents.
The revelations in the documents will give opponents of nuclear power ammunition to argue nuclear plants should never have been built in seismically active zones, NewScientist.com said.