Nuclear power safety: Latest on Japan crisis fuels new concern in US

Nuclear power safety: Latest on Japan crisis fuels new concern in US

...Since then, however, the news from Fukushima has gotten worse. On Sunday, Tokyo Electric Power Co. said the uranium fuel core in its No.1 unit had melted completely – a worse condition than previously believed – and apparently seared a hole in the reactor vessel. Core meltdowns at the No. 2 and No. 3 reactors also are more serious than earlier believed.

Then, on Tuesday, The New York Times reported that the Fukushima reactors had the same hardened emergency vents that NRC officials had said made similar plants in the US safe from hydrogen explosions. The newspaper also reported, in a separate story, that the NRC had been warned years ago that the vents were subject to failure in a crisis.


...The antinuclear group Beyond Nuclear charged that, while some US Mark I reactors possess the same venting systems that failed in Japan's crippled plant, the NRC knows that other Mark I reactor operators may not have installed – or may even have uninstalled – those venting systems. (NRC officials insist all such reactors are equipped with the vents.) If the venting systems at Fukushima Daiichi had worked as designed, they would have prevented damage to containment from the hydrogen explosions, it said.

"The NRC left the retrofit of this experimental venting system to the voluntary discretion of the US reactor operators,” said Paul Gunter, director of reactor oversight at Beyond Nuclear, in a statement. “Now that this experimental containment vent is demonstrated to have failed at Fukushima, we need to know who installed it at US plants, who didn’t, and the justification for the continued operation of these deeply flawed and dangerous reactors."...