Spontaneous Fission In Fukushima Daiichi Unit 2

Kyusaku Natsume writes "Tokyo Electric Power Co. said Wednesday that some of the melted fuel in reactor 2 at the Fukushima No. 1 nuclear plant may have triggered a brief criticality event. Tsuyoshi Misawa, a reactor physics and engineering professor at Kyoto University's Research Reactor Institute, said that if Tepco's data are correct, 'it's clear that the detection (of xenon-133 and -135) comes from nuclear fission.' Tepco spokesman Junichi Matsumoto said the test results suggest that either small-scale fission occurred in the melted fuel, or conditions to trigger criticality were temporarily met for some other reason. He said the same thing could also happen at reactors 1 and 3. But because the reactor's temperature and pressure level have not changed, the fission would not have been large-scale, Matsumoto said, adding that it would not thwart Tepco's schedule for achieving a cold shutdown at the reactors. In response, boric acid water was injected again on November 2. On the plus side, the concentration of radioactive materials in the air is low enough that workers inside some areas of Fukushima Daiichi workers soon will not have to use full face masks."

Comments

Re:No (fission) Nukes

[shish]

my enthusiasm also assumed that the industry was regulated and transparent enough to be safe. Clearly it is not

And other industries are?

Burning coal does far more, further reaching damage - it just does it slowly and constantly as part of normal operating procedure, so nobody cares. (Other sources like solar / wind would be best, but I don't see them being able to fill the whole planet's energy needs any time soon)

Re:No (fission) Nukes

[gstrickler]

Judging nuclear power's safety by a first generation reactor design that was built nearly 40 years ago, and that despite a M9 earthquake and 15m tsunami has not killed anyone, and is predicted to eventually cause up to 100 deaths from cancer is foolish. It's like judging hydro power by the dams that have burst and flooded and killed thousands, or by natural gas pipeline explosions that have killed hundreds, yet you're not protesting those types of power.

Nuclear power has caused fewer deaths per TWh generated than any major power source, including wind, solar, geothermal, hydro, or fossil fuels. Nuclear power is the safest power source yet tried, and that's even with the older reactor designs and the Russian RBMK design (e.g Chernobyl) that is inherently unstable and should never have been built.

Gen III reactors have passive safety designs that allow full cold shutdown with no external power. And thorium fueled reactors don't produce usable quantities of plutonium so they're not a proliferation concern, and doesn't require uranium enrichment (which is itself expensive and dangerous). And using fuel reprocessing dramatically lowers the nuclear waste (by a factor to 10 to 100).