How TEPCO pulls this off remains a mystery to me. Radiation levels inside the reactor buildings go up and down, but on average they seems pretty darn high as a working environment. In the US, the additional annual dose a worker in the nuclear industry is allowed to be exposed to is 50,000 µSv per year, internationally and in Japan prior to the accident that maximum level is (or has been) 100,000 µSv per year. Japan raised that maximum allowable level to 250,000 µSv/year, even though it is well-known that cancer risks undeniably start at over 100,000 µSv/year extra.
Japan Today (April 18, 2011 in Japan) reported once again “elevated levels”: http://www.japantoday.com/category/national/view/elevated-levels-of-radiation-measured-inside-reactor-buildings: [my emphasis] “…The Nuclear and Industrial Safety Agency suggested that the readings—measured at between 10 and 49 millisieverts per hour for the No. 1 unit and between 28 and 57 millisieverts per hour for the No. 3 unit—put time constraints on any work that must be done inside the reactors.” Another reading mentioned was “270 millieSievert”, somewhere “near the door to the No. 1 reactor building…”
Let me “translate” that for you: in microSievert per hour –> max yr dose reached in:
Unite 1: 10 – 49 millisieverts per hour = 10,000 – 49,000 µSv/h –> 25 – 5 hrs
Unit 1 “by the door: 270 mSv/h = 270,000 µSv/h –> 55 minutes
Unit 3: 28 – 57 millisieverts per hour = 28,000 µSv – 57,000 µSv/h –> 9 – 4.5 hrs
So whoever works in such “maximum allowable levels reached within 1 hour to a couple days (of shifts)” environment should be replaced with a new willing worker (after less than a day of exposure!) to work in such a toxic radioactive disaster site. Where do they keep getting willing skilled replacement workers?
Oh… I see: They’re not even working in there. A pair of robots, called Packbots, made by iRobot in Bedford, Massachusetts (go figure, I though the Japanese were the leaders in robots?) went in and took those readings. Good they’re not using workers as canon fodder, but… then… um… Not much really can even have possibly changed… if they haven’t even been able to work inside the buildings. When will they? (And… So what happened to the courageous 50 Kamikaze heroes?)
TEPCO’s Plan: 3 months to reduce the radioactivity levels, then another 3 – 6 months to get the reactors to fully shut down (a.k.a. end the de facto meltdown situation). So maybe by New Year 2012 the volatile crisis situation will be over, and then rests securing this radioactive mess for the next tens of thousands of years… And that’s if no big aftershock or unforeseen glitch ruins the plan…
Nuclear Energy’s last stand. Finally.
SOURCE for plan basics: http://www.cnn.com/2011/WORLD/asiapcf/04/17/japan.nuclear.reactors/