Contamination dropping in evacuation zone (Japan)

[FBaggins]

Analysis from Japan's Nuclear Regulation Authority (NRA) has revealed the most contaminated areas in the Fukushima evacuation zone have reduced in size by three quarters over the last two years. Data comes from a series of helicopter surveys carried out on four occasions across the two years that followed the March 2011 accident at Fukushima Daiichi. Instruments trained on the ground captured radiation readings which were combined with GPS locations and adjusted for altitude variation to create maps for comparison.

Most obvious from the sequence of maps is the progressive reduction in the size of the red portion, which represents high radiation dose rates of over 19.0 microSieverts per hour (uSv/h) - some 166 milliSieverts per year (mSv/y). These went from covering 27% of the 1113 square kilometer zone to just 6% between 5 November 2011 and 11 March 2013. All these higher activity areas are within towns and villages categorised as 'difficult to return to'.

...snip...

Finally the less contaminated areas, described as 'preparing to lift the evacuation order', are now entirely below 3.8 uSv/h. This equates to a dose of 33.2 mSv/y, which remains higher but within reach of the proposed criteria of 20 mSv/y for return.

Apart from radioactive decay, natural processes have also contributed to reducing levels of contamination since the accident in March 2011. Rainfall moves contamination through river systems to the sea, where strong currents and a powerful dilution effect make radioactivity virtually undetectable even alongside the damaged power plant itself.




http://www.world-nuclear-news.org/RS_Contamination_dropping_in_evacuation_zone_0706131.html

[RobertEarl]

1. That is a hilarious report... not

Actually it is sickening that all that land is and was so polluted and now the Pacific is polluted, too.

And for what? To keep the lights on for a few years? What a waste of money and land.

And where is the mention that 150,000 people have been forced from their homes? Why isn't that fact in your OP?

[FBaggins]

2. Hilarious better describes your knee-jerk response.

Radiation levels are down substantially. Isn't that a good thing?

And where is the mention that 150,000 people have been forced from their homes? Why isn't that fact in your OP?

Maybe because it was an article about radiation levels and not one about evacuees?

But actually it does mention them. Who do you think is impacted by "preparing to lift the evacuation order" ?

[RobertEarl]

3. Just shows where you concern lies

Not one whiff of concern for the 150,000 plus, or the Pacific, just a concern that nuclear power become accepted again.

Newsflash: Nuclear power is dying. It is like the dinosaurs in that the remains will be able to be recognized millions of years from now.

[FBaggins]

4. Newsflash... you aren't living in reality.

Still can't get that visa approved, eh?

Nuclear power isn't dying. It's expanding in many areas of the world. It isn't expanding as fast as some of us would like... and a wave of retirements from faster construction decades ago will hide the industry's growth for years to come... but it's hardly dying.

Must drive you crazy that there are five new reactors under construction within spitting distance of you (one almost in walking distance, right?). How much time do you spend on the back porch yelling into the winds of progress that they're supposed to be dying?

Oh... and let's not forget two more reported on just a couple days ago. How close are they to you?

http://www.timesfreepress.com/news/2013/jun/02/is-smaller-better-for-nuclear-reactors/

Be honest now. Ten years ago... how many reactors did you think would be under construction now in the US? Seems to me that I remember a previous incarnation telling me that Vogtle and Summer would never be built and SMRs were a pipe dream.

[RobertEarl]

5. Yes Nuclear is spreading

It has spread all around the world. Even the EPA admits that nuclear pollution from Fukushima landed in the US.

The industry is dying. I am happy as can be about that. SONGS is shut down!! Crystal River, down and out. There has not been one new plant built in the US in 30 years. Vogtle will never open. Last I heard it's reactor core fell off the tracks.

It costs too much. People are using less electricity, but using more solar, everyday.

[FBaggins]

7. The EPA "admits" that, eh?

They also report correctly that it's in irrelevant amounts - far FAR lower than what was already here.

There has not been one new plant built in the US in 30 years.

And yet there are five under construction and more to come. Is that in the general direction of "dying" or "growing"?

Vogtle will never open. Last I heard it's reactor core fell off the tracks.

As usualy... you "heard" wrong. (voices again, eh?)

Unit 3 is almost half complete and the RPV (not the "core&quot is on site waiting to be installed.

People are using less electricity

I once again invite you to visit reality once in awhile. Electricity demand is not shrinking (here or globally). There was a very short dip during the recession, but all we've had success with so far is a reduction in the rate of growth.

Last I saw, consumption was up about 5% this year over last.

[kristopher]

6. Keywords: nuclear power; contamination; evacuation zone nt

[quadrature]

8. numbers to keep in mind

a typical American gets a dose
of 6 milli-Sievert of rad, from all sources,
of which about 1 mS would be from
what I would call
'just standing around and breathing'.

there are about 8800 hours in a year.

if your are standing in the 1 micro-Sievert per hour
zone, that is 8.8 milli-Sievert per year

[wtmusic]

9. Yellow zone residents get about the same amount of radiation as living in Colorado. nt

[quadrature]

10. I have seen that statement before.

perhaps you, or somebody,
can help me flesh that out
with some numbers.

the numbers I have don't add up
exactly that way, I`` need to know
the assumptions used. thanks.

[wtmusic]

11. My bad, lame conversion.

Sorry for the long link:

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=4&cad=rja&ved=0CEwQFjAD&url=http%3A%2F%2Fwww.ucdenver.edu%2Facademics%2Fcolleges%2Fmedicalschool%2Fdepartments%2FRadiology%2FDocuments%2FUniversity%2520of%2520Colorado%2520Radiology%2520Dose%2520Smartcard.pdf&ei=lvK1UcP3J6vqiwKKwoDIDw&usg=AFQjCNE6XeCPuVO1OfgMsTh5USgK28YrFw&sig2=dN5oUsnfuNor0Sm1AtLZCA&bvm=bv.47534661,d.cGE

State of CO ~ 4 mSv/year.

Extrapolating yellow area to yearly rate = about 36 mSv/year.