Radioactive cesium found on S. Korean streets

[kristopher]

Radioactive cesium found on S. Korean streets
November 05, 2011
By AKIRA NAKANO / Correspondent

SEOUL -- South Korean authorities began digging up streets in Seoul’s Nowon Ward on Nov. 4, after high radiation levels were detected on the asphalt.

Employees of the government-affiliated Korea Institute of Nuclear Safety on Nov. 4 dug holes to collect samples of the road surface at intervals of about 5 meters along a 200-meter stretch of a shopping street in the Weolgye-dong district.

Radiation levels of 2.7 microsieverts per hour on the road surface and 1.8 microsieverts per hour at a height of 1 meter above the ground were measured near the front gate of the Induk industrial high school, which is on the road.

Officials said it was likely that the radiation source was cesium-137, which has a half-life of 30 years. It is suspected that the aggregate used to make the asphalt may have been contaminated with the radioactive material...

http://ajw.asahi.com/article/0311disaster/fukushima/AJ2011110816850

[nadinbrzezinski]

1. Ok I am confused...and it is geography.

That is all...oh and wind direction.

[Ian David]

2. All contaminated roads were found to have been paved around 2000.

[nadinbrzezinski]

3. Which has nothing to do with Fuku.

Means somewhere else this came from.

Look at the link in op for source of confusion (and I linked on it as well)

[kristopher]

6. OP also dates the problem as being preFukushima as they found another rd in Feb 2011

However, that raises the question of what nuclear reactor THIS cesium escaped from, doesn't it?

Do you have a link for the 2000 date?

[Ian David]

7. It's in the original article. n/t

[kristopher]

8. Don't know how i missed that.

Thanks.

[FBaggins]

9. NK weapons testing perhaps?

Though 2000 seems early for that.

[kristopher]

10. How many reactors did S. Korea have in operation in 2000?

[FBaggins]

15. All but the newest handful

That's even less likely.

[Yo_Mama]

11. It's usually medical waste, improperly disposed of

Cesium 137 is used in medical devices, and there was a nasty incident in Mexico not that long ago. But it is also used in industrial applications and devices.

http://www.qsa-global.com/sources/industrial-isotopes/cesium-137.aspx

The Cesium-137 would originally have come from a reactor, but the asphalt contamination would have occurred as an improper disposal of devices containing the isotope. (Or a failure of the device in situ, perhaps?) CDC link:
http://www.bt.cdc.gov/radiation/isotopes/cesium.asp

[kristopher]

13. Or an undisclosed incident at a power reactor - you haven't got an effing clue of the source.

At this point no one, including you, knows *anything* about where that material came from, except that it is man made in a reactor. You hope it didn't come from an power reactor, but that is all you have - hope.

[FBaggins]

14. As usual, you have that almost exactly backwards.

It's you that allows your hopes/fears to influence your perception of reality.

Let's take as an example, your useful thread asking "What do we KNOW about the environmental effects of fracking?". It's an excellent question to ask, but you start the thread off by assuming that we "know" two things... that they are "concrete information". The reality is that neither one is something that we "know". They are initial theories by one source (each) that are contradicted by others. But you allow your predisposition against fossil fuel use to bias your acceptace of those early theories as something that we now "know". I share your predisposition (in this case), but that doesn't change reality. As a second example, take the only thing that you claim we do know in this case... that it was man-made in a reactor. Even that is not true. It's likely to be the case, but as of this reporting they were only assuming that it was cesium.

To return to the current subject, let's review a few things that we do, in fact, "know".

- The vast majority of cesium in the environment (by which I mean not in reactors, spent fuel, etc.) is from weapons testing over the last several decades. So if you find cesium in small concentrations it isn't at all unreasonable to assume that that's where it came from. It's certainly far more reasonable than assuming that a reactor accident occured somewhere and was covered up.

- This isn't the first time that this has occured. "The Institute of Nuclear Safety has previously reported that cesium-137 has been detected over the past 10 years in South Korea's air and soil when so-called yellow dust blows in from China"

- The amounts are reported as ten times background levels. Presumably that isn't background levels of cesium, but rather overall radiation (making the cesium contamination likely hundreds of times above normal). Post Fukushima reporting has shown us clear evidence that some processes (particularly sludge incineration) can concentrate cesium contamination many hundreds/thousands of times... and that the remaining material is sometimes used in road construction. So there's a plausible path for normal background cesium (from weapons testing in prior decades) to produce these results.

Now let's take the contrary argument and see how it stands up. You propose the possibility that a S Korean reactor (the closest is about 150 miles away) had an accident that released cesium over a large area... but didn't disable the reactor in any lasting way... and the government covered it up so masterfully that nobody had any clue (and other countries that would have detected the release were presumably convinced to keep quiet). , although they did such a great job of keeping the secret, they... oopsie!... made this announcement public without realizing that they were giving away the whole game.

Which seems more likely to you?

[kristopher]

16. More of your pretense and nonsense?

Leaving aside your incomprehensible references to the thread on fracking...

Your claim I'm "assuming" any source is a product strictly of your obsession with attacking me Baggins. The post is short and clear; in response to a claim that the cesium "would have" come from improper disposal of some sort of device I wrote:
"Or an undisclosed incident at a power reactor - you haven't got an effing clue of the source. At this point no one, including you, knows *anything* about where that material came from, except that it is man made in a reactor. You hope it didn't come from an power reactor, but that is all you have - hope.

no one 
noun
no person; not anyone; nobody

That included you and it includes me.

And then we have your characterization of what I've supposedly "proposed".
"You propose the possibility that a S Korean reactor (the closest is about 150 miles away) had an accident that released cesium over a large area... but didn't disable the reactor in any lasting way... and the government covered it up so masterfully that nobody had any clue (and other countries that would have detected the release were presumably convinced to keep quiet). , although they did such a great job of keeping the secret, they... oopsie!... made this announcement public without realizing that they were giving away the whole game."

Take a look at that Baggins. Now compare it to what I wrote: "an undisclosed incident at a power reactor". What you've done is create an elaborate "red herring" that is designed strictly for the purpose of yet again attacking me.

The actual type of incident I was considering was the possibility that a small local event might have contaminated blacktop at a plant and after clean-up the waste asphalt was improperly disposed of and ended up being recycled.

[FBaggins]

17. Nope just correcting your misperception of what is "known"

vs what you assume.

in response to a claim that the cesium "would have" come from improper disposal of some sort of device

Yep. In response to one poor assumption, you expanded the universe of possibilities for consideration to two poor assumptions... while ignoring a far more plausible possibility. Congratulations.

By far the most likely source remains weapons testing. The additional reporting of "yellow dust" makes that even more likely. They've been finding cesium in it for at least a decade and virtually all of China's weapons testing was done in the desert west of Korea. You can see plumes of yellow dust flowing seasonally from the Gobi, the Yellow River Valley and Lop Nur area for thousands of miles (right over Korea). This is only slightly harder than putting two and two together. Surely it's not beyond you?

At this point no one, including you, knows *anything* about where that material came from

And that was wrong. We don't know where it came from (because we don't even "know" what it is), but we do know something about it.

Take a look at that Baggins. Now compare it to what I wrote:

The only significant different is whether the accident spread contamination over 150 miles or just locally (and then somehow the asphalt ended up 150 miles away). It isn't a "red herring" at all. You propose a nuclear power accident that was successfully covered up until whoops! someone slipped and released this news.

[dtexdem]

4. I've heard of paving the streets with gold, but this is ridiculous.

[Hestia]

5. Couldn't the cessium have been blown in by the typhoons they've had in the area? Quite plausible

[Yo_Mama]

12. No, it isn't plausible at all

At the time the road was paved, there wasn't enough ambient cesium around in the atmosphere to have caused cesium contamination. Read the whole article. The cesium is in the asphalt; the road was paved in 2000.

I suppose there is some faint chance that this could date back somehow to Chernobyl deposits - there is some Chernobyl contaminated steel out there.