Tepco battered by media storm

Wednesday, 18 July 2007 Tokyo Electric Power Company (Tepco) has endured a media storm since the earthquake of 16 July, which was centred just 19 km from one of its plants.

The earthquake, rated at 6.8 on the Richter scale by Japanese scientists, killed ten people, injured 1100 and forced 13,000 from their homes. Much infrastructure was damaged including many vital roads and railways. Authorities have now begun to airlift aid to residents living without power or water as well as those who had lived among the 300 buildings that were destroyed.

Just 19 km from the epicentre of the earthquake, Tepco's Kashiwazaki Kariwa plant was violently shaken. The earthquake exceeded the plant's design basis - the levels of ground acceleration it should essentially withstand and restart operation quickly after - but did not approach its safe shutdown basis, up to which environmental protection must be maintained in the most extreme circumstances.

The four reactors in operation at the plant shut down automatically, but an electrical transformer failed and caught fire and drums of solid low-level radioactive waste fell from position. Vibrations also caused a total of 1.2 cubic meters of water to spill from three of the plant's used nuclear fuel cooling ponds, and be discharged to sea.

Akira Fukashima, head of Japan's Nuclear and Industrial Safety Agency (NISA), has said that no hazardous abnormalities have been found at the site.

Despite the safe shutdown and the absence of serious injury on site, Tepco has faced fierce criticism worldwide. First, media attention was drawn to the transformer fire, then the release of cooling pond water, and finally focused on the disruption in the low-level waste store. In some reports the events at the nuclear power plant garnered more attention that those of the earthquake as a whole.

"Much of the media has gotten this story backwards," said John Ritch, director general of the World Nuclear Association. "Rather than spawning doubts about the safety of nuclear energy, this event offers substantial reassurance. Even the severest earthquake - directly affecting the world's largest nuclear power plant and far beyond anything anticipated - did not jeopardize the public or the environment."

"The plant's much-exaggerated 'radioactive leak' consisted of a tiny volume of liquid only three times more radioactive than ordinary table wine, and the total leakage involved an amount of radioactivity that can be found in three smoke detectors," Ritch continued.

One issue has been Tepco's communications effort, which has been criticised for being too slow and for being inaccurate. The release of pond water was not reported for six hours, while the amounts of radioactivity in the water had to be upwardly revised by 50% due to a miscalculation. Similarly, statements on the waste barrels went from describing 100 disturbed and a few open, to hundreds disturbed and dozens open.

Japanese prime minister Shinzo Abe said: "Nuclear power can only operate with people's trust" and that power companies must "accurately and swiftly report what is happening."

Kashiwazaki mayor Hiroshi Aida, who holds power over nuclear operations in the area, has said the plant must remain shut until safety is assured.

Meanwhile, Tepco and officials from the NISA are conducting checks in accordance with procedures. The company has catalogued over 50 points of damage sustained across the seven-reactor site, but has not yet compiled a work schedule for the necessary repairs.

Further information

Tokyo Electric Power Company (Tepco)

WNA's Nuclear Power in Japan information paper
WNA's Nuclear Power Plants and Earthquakes information paper

WNN: Kashiwazaki Kariwa nuclear units shut down on earthquake