Record High Radiation Unit 1 – 512 Sv/h, No Cold Shutdown, 30km Evacuation Zone Ended

We have been following the reactor data and previously posted about the high radiation levels that appeared in unit 1 after earthquakes near the plant. One had a 17 Sv jump after a quake. Another quake caused a 57 Sv jump. We also outlined the ongoing concern about what this may mean related to the location of the melted fuel. Now today, after the 5+ earthquake yesterday readings in the drywell of unit 1 are a whopping 512 Sv. This does fit with a pattern we have seen of gradually rising drywell radiation with major spikes after each earthquake. This pattern is unlikely to happen in a faulty gauge. (image of the radiation readings graph at the end of the post.) A likely reason for these high readings is melted fuel mass somewhere near the gauge in the drywell.

By contrast, at Chernobyl readings shortly after the explosion were lower, though in this incident much of the fuel was ejected in the explosion. The highest reading was 300 Sv near the core region after the explosion in Chernobyl. The area near the unit was 10-15 Sv/h. Anything above 10 Sv/h is certain death, .25 to 10 Sv/h is probable death.

At the same time the media has been busy telling everyone that Fukushima is in “cold shutdown”. Cold shutdown is a term used on an intact reactor that still contains fuel that is below 200 degrees Fahrenheit and at atmospheric pressure. It clearly does not qualify in a case where the fuel is known to be melted through the bottom of the reactors and TEPCO has no official clue where the melted fuel is. The admission of melt throughs has been heavily documented and repeated by the IAEA and a number of other agencies. Such as outlined here.

Cold shutdown is a clearly inappropriate term. “Stable” might be more accurate if they feel they have control over the units. Without a location of the fuel, stable may also be slightly hopeful. About two weeks ago TEPCO changed their water injection system to core spray. Now they are quickly declaring “cold shutdown” because the reactor vessels are below 100 Celsius. If the fuel is outside of the reactor vessel all that has been accomplished is cooling of the empty metal vessel.

Citing major progress after a week of pushing the cold shutdown myth, the government has lifted the 20-30km zone.  The reaction of the local population seems to be more concerned about the lack of an organized decontamination plan for the area to make is habitable.

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