Soil, grass, and seaweed updates 6/9

Submitted by bandstra on Thu, 2011-06-09 23:10

6/9 (11:10pm): Food chain samples have been updated with new samples of topsoil, grass, and seaweed. Cesium-134 and 137 were detected in the soil sample, but no fission product isotopes were detected in the grass or seaweed samples.

Mark [BRAWM Team Member]

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Good Data

Submitted by Bill Duff (not verified) on Fri, 2011-06-10 08:32.

.

We expect to see 'scatter', 'bounce' and statistical anomalies in any valid data set.

'Railroad Tracks' look pretty, but natural processes do not always go in straight lines.

A few drops of rain, whirlwind, hearby construction or even a leaf-blower would stir up enough dust and radioactive fallout to cause such bounces.

Good science and good laboratory technique will usually produce some 'outlier' data.

Keep up the good work!

So... After trending

Submitted by Anonymous (not verified) on Fri, 2011-06-10 00:16.

So... After trending downward over the last three samples / eight weeks, cesium-134 and -137 bounced higher -- by 25 to 50%. Any thoughts on this? One measurement does NOT necessarily a trend make, naturally -- but if you good folks at BRAWM were to decide to make more frequent topsoil testing a near-term priority, I very much doubt if anyone here would argue.

Great news on the grass and seaweed. I am VERY interested to see the results of the next few air samples.

Continue to appreciate y'all, very much indeed.

Rick Cromack.
Allen, Texas

On the Rise: Highest level

Submitted by Anonymous (not verified) on Sat, 2011-06-11 18:03.

On the Rise: Highest level of Cesium-137 in Bay Area topsoil since April

http://enenews.com/rise-highest-level-cesium-137-bay-area-topsoil-april

Level consistent with previous measurements

Submitted by bandstra on Sat, 2011-06-11 18:46.
I am a stickler for error bars, as some readers of the forum may know by now, and so I don't like it when BRAWM measurements are quoted without their error bars. This might seem like a subtle point, but it is not — if error bars are taken off the data, the data themselves lose all context. In this case the headline is entirely wrong. Here is what that headline should say: "Recent measurement of Cesium-137 in Bay Area topsoil consistent with previous measurements."
BRAWM Topsoil data
Sample DateCs-137 Activity (Bq/kg)
6/3/111.17±0.12
5/18/110.73±0.07
5/2/111.11±0.11
4/21/111.21±0.12
4/13/111.16±0.12
4/8/110.90±0.12
4/6/111.53±0.15
The 6/3 measurement is not the highest measurement since April — it is actually consistent with almost all of the other topsoil measurements. You can see pretty clearly from the error bars that the 6/3 measurement is significantly higher from the 5/18 measurement, but consistent with the 5/2, 4/21, and 4/13 measurements. The 6/3 measurement is significantly above the 4/8 measurement but significantly below the 4/6 measurement, but just barely in both cases. But this is makes for a much more boring headline... Mark [BRAWM Team Member]

So American soil is still

Submitted by Anonymous (not verified) on Mon, 2011-06-13 07:06.

So American soil is still contaminated with radioactive cesium. While an industrialist at heart, a resigned CFO with a passion for technological process and a penchant for all the finer things, I am glad I had the courage early on this crisis to move the family South. America shall see us again, but not any time very soon.

I admit it's awe-inspiring to think of what damage has been done to the continent of North America in just the past 100 years. My God!

The technological process

Submitted by Anonymous (not verified) on Mon, 2011-06-13 07:09.

The technological process too, but I meant progress.

Data in perspective

Submitted by Jonathan (not verified) on Sat, 2011-06-11 22:01.

Thanks very much for a clear discussion of what the data mean. I see now the significance of the error bars in the measurements and how essential they were in how the data are interpreted.

You are going to lose all your sponsors, Mark

Submitted by Anonymous (not verified) on Sat, 2011-06-11 18:58.

Perhaps jazzing up your headline a bit will keep people rivited? Something like:

"Recent measurement of Cesium-137 in Bay Area topsoil is ALARMINGLY consistent with previous measurements"

Like with most sensational headlines, it will rope them in. And then, after actually looking at the data, they'll find out that the excitement ends with the headline.

Topsoil Cs-137 Higher Then Early April

Submitted by Anonymous (not verified) on Fri, 2011-06-10 06:43.

What concerns me is that the latest topsoil results (1.17 Bq/kg) for Cs-137 are higher than the 4/8 (0.90 Bq/kg), 4/13 (1.16 Bq/kg) and 5/2 (1.11 Bq/kg) results. The latest Cs-134 (0.58 Bq/kg) result is only higher than the 4/8 result (0.41 Bq/kg).

BRAWM team, any idea what caused this uptick?

I'll hazard a guess. Soil

Submitted by BC (not verified) on Fri, 2011-06-10 07:32.

I'll hazard a guess.

Soil composition.

And hopefully someone smarter than me on the BRAWN team can confirm that:).

Thanks, Mark! Looking

Submitted by Anonymous (not verified) on Thu, 2011-06-09 23:35.

Thanks, Mark! Looking good.

Just a question, is it possible to calculate surface contamination from the topsoil sample?

Not without original sample dimensions

Submitted by Earthquakeprepper (not verified) on Fri, 2011-06-10 21:10.

Papers on Chernobyl soil contamination are usually measured per square meter, often with depth included.

Without that information it is not possible to make comparisons with U.S. contamination immediately or over time.

Also I believe the grass samples are coming from a mowed, watered lawn. So their direct comparison to pasture grass used for grazing would be somewhat tenuous.

fission product isotopes =

Submitted by Kell (not verified) on Sat, 2011-06-11 18:06.

fission product isotopes = radioactive isotopes?