The NRC went to work — not figuring out how to fix the vessels, but justifying a higher standard

[NNN0LHI]

http://www.google.com/hostednews/ap/article/ALeqM5hfR-TuckDtA0JIf_x_Cy0tw6nkWg?docId=5042dd7273d9493ea4787485e5d99468

Radiation bombards reactors, make them brittle

By JEFF DONN, AP National Writer – 5 hours ago

No aging problem has been more vexing or dangerous in nuclear power plants than the tendency of reactors to grow brittle. snip

The U.S. Nuclear Regulatory Commission decided to set a 200-degree Fahrenheit benchmark known as "reference temperature" — a calculated measurement that predicts the threshold at which the vessel could break apart. The higher the reference temperature, the more likely the coolant will crack the vessel.

By 1982, 14 nuclear plants had violated the standard. An NRC staff report offered the faint reassurance that no shutdowns would be needed "in the next few years."

The agency went to work — not figuring out how to fix vessels, but justifying a higher standard.

This still wasn't enough...

[Wilms]

1. At the bottom of the linked paged is a similar story.

Nuclear wear makes accidents more likely, AP finds

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In 1982, U.S. Nuclear Regulatory Commission staff reported that reactor after reactor was failing leak tests, and backup systems weren't always working.

snip

Yet talk within industry and government isn't centered on replacing the valves more frequently. Instead, they are discussing lifting limits again.

snip

http://seattletimes.nwsource.com/html/nationworld/2015371334_apusagingnukesleakyvalves.html