Nuclear Crisis In Japan: Disaster Threat Decreasing

Mar 21, 2011, 14:17 by David Hope

The ongoing nuclear crisis in Japan has not completely ended - but the threats appear to be subsiding a bit. While the situation at Japan's Fukushima nuclear power plant remains "very serious" the head of the United Nations' nuclear advisory body expressed hope Monday that the crisis would be overcome.

"I have no doubt that this crisis will be effectively overcome. Nature can be cruel but human beings are brave, resourceful and resilient, "said Yukiya Amano, director general of the International Atomic Energy Agency, in an emergency agency meeting Monday in Vienna, reporting on his visit to Japan last week.

However, he said governments need to improve how they respond to such crises in the future.

Attempts continued to cool reactors and spent fuel ponds at the Fukushima plant, after the facility's cooling system was knocked out by the March 11 earthquake and tsunami.

On Monday, however, smoke was seen rising from the plants No. 2 and 3 reactors, hampering efforts to cool them.

Plant operator Tokyo Electric Power Co. said it had briefly evacuated its workers after the smoke was spotted, Kyodo news reports.

A Wall Street Journal analysis of Japanese regulatory documents shows that Fukushima was one of the country's most trouble-prone nuclear facilities prior to the quake.

Takeshi Makigami, head of Tepco's nuclear-equipment-management section told the Journal the main reason the Fukushima plant doesn't fare well in the analysis is because "they're old reactors."

All of the plant's reactors came online during the 1970s. Since 2005, the plant has had 15 accidents, the analysis of data from the Japan Nuclear Energy Safety Organization indicates. But none of the incidents were considered major safety hazards or resulted in the release of any radioactive material outside the plant until the earthquake this month.

For example, in 2007 an emergency diesel generator began smoking during a test, the Journal reports. A subsequent investigation found that part of the generator's circuit breaker had been assembled backward. The failure of Fukushima's generators -- which power water pumps critical to reactor cooling systems � is seen as a leading cause of the facility's crisis.

The regulatory documents also show that over the last decade, Fukushima's employees have been exposed to more radiation than those working in other nuclear plants in Japan.

Because Fukushima has older reactors, it had needed more frequent repairs and checks compared to new nuclear plants, said Teruaki Kobayashi, an official with Tepco's nuclear-plant-management section told the Journal. Also, because the plant is of an old design, he said, "radiation tends to be higher."

"When we carry out major improvements or checks, inevitably people are more likely to receive radiation," he said. "That's because some tasks can only be done by human hands."

Source: UPI