The New York Times reports on new comments from the U.S. Nuclear Regulatory Commission chairman on the radiation threats from failing nuclear power plants in Japan. The radiation levels are “extremely high” at Fukushima No. 4 reactor’s spent fuel pool, he said. The NRC is now recommending evacuation for Americans within 50 miles of the Fukushima power plant. (Note, however, that officials today said the chances of radiation traveling 5,000 miles across the Pacific Ocean to Oregon are “extremely slim”)
Gregory Jaczko, the chairman of the commission, said in Congressional testimony that the commission believed that all the water in the spent fuel pool at the No. 4 reactor of the Fukushima Daiichi Nuclear Power Station had boiled dry, leaving fuel rods stored there exposed and bleeding radiation. As a result, he said, “We believe that radiation levels are extremely high, which could possibly impact the ability to take corrective measures.”
If his analysis is accurate and Japanese workers have been unable to keep the spent fuel at that inoperative reactor properly cooled — it needs to remain covered with water at all times — radiation levels could make it difficult not only to fix the problem at reactor No. 4, but to keep workers at the Daiichi complex from servicing any of the other problem reactors at the plant.
Mr. Jaczko (the name is pronounced YAZZ-koe) said radiation levels may make it impossible to continue what he called the “backup backup” cooling functions that have so far helped check the fuel melting at the other reactors. Those efforts consist of using fire hoses to dump water on overheated fuel and then letting the radioactive steam vent into the atmosphere.
Those emergency measures, implemented by a small squad of workers and firemen, are the main steps Japan is taking at Daiichi to forestall a full blown fuel meltdown that would lead to much higher releases of radioactive material.
Mr. Jaczko’s testimony came as the American Embassy in Tokyo, on advice from the Nuclear Regulatory Commission, told Americans to evacuate a radius of “approximately 50 miles” from the Fukushima plant.
The advice represents a graver assessment of the risk in the immediate vicinity of Daiichi than the warnings made by the Japanese themselves, who have told everyone within 20 kilometers, about 12 miles, to evacuate, and those between 20 and 30 kilometers to take shelter.
Today, OPB’s Rob Manning reported Oregon public health officials assessment of the “extremely slim” risk of radiation traveling 5,000 miles across the Pacific Ocean and affecting Oregonians:
“Public health officials say radiation would have to make a 5,000-mile journey from Japan to the Northwest. Officials say such a trip could take a week.
But they say chances that nuclear material would cross the Pacific are “extremely slim.”
Officials contend the radiation releases would have to be much bigger, and would have to go far higher into the atmosphere to pose a realistic threat.”