[tlug] Measuring radioactivity at TEPCO Fukushima plant

["Stephen J. Turnbull" <stephen@example.com>]

I think this has been published already on this list, but
"nen-no-tame" I'll post the URL again.  You can get TEPCO's latest
press releases, most importantly gamma and meson emissions in
micro-sieverts at Power Stations #1 (the one with all the explosions,
and a 20km evacuation radius) and #2 (the 10km evacuation radius), at

http://www.tepco.co.jp/cc/press/

I don't know if I really trust the numbers, since they are almost
monotonically decreasing.  Yesterday's numbers did show a brief but
small spike around noon, but it's hard to evaluate since they were
apparently moving the sensor around.  (They've only got one?!!?  Or
maybe the person maintaining the page read fixed sensors in some more
dangerous places before sticking to the safer West Gate sensor?)  Note
that there are at least four difference locations mentioned (Main
Gate, West Gate, Gym, and Admin Offices North side yesterday), so be
careful about trying to assess trends.  Today, all Fukushima Power
Station #1 readings were taken at the West Gate.

On the other hand, "almost monotonically decreasing" is what you would
expect if things were (somewhat) under control and the fuel rods were
gradually cooling.  You'd get brief but small spikes based on wind
direction changes etc.

Finally, if these are at all based in reality, note how fast the
readings decrease with distance: from 4000 microSv/hr at the admin
office to 300microSv/hr.  That won't be all that much comfort if
things really go south and a big cloud of radioactive dust starts
moving, but at least there's some comfort for people in that area of
Fukushima-ken as long as the temperature remains somewhat controlled.

Steve