Japan's Earthquake - and Radiation Leaks

By NORIMITSU ONISHI / from The New York Times

TOKYO — A powerful earthquake shook Japan’s northwestern coast on Monday morning, killing at least nine people and injuring more than 900, flattening hundreds of buildings and leaving thousands homeless.

The earthquake also caused a small fire at a nuclear power plant, the world’s largest, which later leaked a small amount of water containing radioactive materials into the Sea of Japan.

The company operating the plant said the radioactivity level posed no danger to the environment, but it delayed acknowledging the leak for several hours.

Television commentators criticized the company’s delay in reporting the leak, which was likely to raise fresh concerns about the safety of Japan’s nuclear reactors. Japan depends greatly on nuclear power, and its nuclear industry has long been afflicted by scandals and cover-ups.

The earthquake was centered off the cost of Niigata, a prefecture that was hit by a devastating earthquake in 2004.

Skyscrapers here in Tokyo, about 130 miles southeast of Niigata, swayed for almost a minute.

Japan’s meteorological agency said the magnitude was 6.8; the United States Geological Survey put it at 6.6.

The tremor occurred at 10:13 a.m. on what was a national holiday here. It caused minor tsunamis and buckled roads and bridges. It also toppled one local train and shut down service on the bullet train for several hours, as well as interrupting the supply of power and water to tens of thousands of homes.

Nuclear reactors in the affected area shut down automatically, but the quake caused a small fire at an electrical transformer at a nuclear plant in Kashiwazaki, a coastal town close to the quake’s epicenter.

Japanese television stations showed flames and black smoke billowing from the nuclear plant, which is operated by Tokyo Electric.

Also: Japan Quake Overturned Drums of Nuclear Waste

On Tuesday, officials said about 100 drums containing low-level nuclear waste fell over at the plant during the quake. They were found a day later, some with their lids open, said Masahide Ichikawa, an official with the local government in Niigata prefecture.

A spokesman at Tokyo Electric Power Co., which runs the plant, said the company was still trying to determine whether any hazardous material had spilled but said there was no effect outside the plant.

''We have no information at this time that there is any effect on the outside environment,'' TEPCO spokesman Manabu Takeyama said.

And: Japanese nuclear reactor under-designed for earthquake?

...Based mainly on historical precedent, TEPCO designed the reactors at Kashiwazaki-Kariwa assuming that the area would have a maximum ground acceleration of 274 gal. Yesterday, the number 1 reactor at Kashiwazaki-Kariwa experienced an acceleration of 680 gal as the ground slid from east to west; the number 5 reactor accelerated at 442 gal east/west, and the number 6 reactor was hit with 488 gals up/down, as measured on site.

TEPCO is in the middle of re-evaluating the safety of its reactors in line with new guidelines implemented in Japan in September 2006, which call for more stringent safety measures. Surveys of active faults now have to take into account earthquakes going back 130,000 years, for example, compared with the previous standard of 50,000 years. TEPCO plans to finish this re-evaluation by December 2008. Whether this re-evaluation would have affected the maximum 'gal' limit for Kashiwazaki-Kariwa remains unclear....