Estimate of total amount of radiation that fell down here during the last rainy period

Submitted by Anonymous on Wed, 2011-03-30 00:18

Berkeley Radiological Air and Water Monitoring Forum

A: Bay Area has a area of 7000 square miles, or 1.8 x 10^10 square meters.
B: Assuming the rain was 10 inches to 20 inches deep; I will take an average of 15 inches, which is 0.38 meters.
C: the average I131 concentration is around 7 Bq/L, or 190 pCi/L, or 1.9E5 pCi/m3.

So here we go:

A*B*C=1.3E15 pCi, or 1,300 Curie I131.

(That's 72 nCi per square meter).

To put it in context:

3 mile island: 17 curie total release.

Fukushima as estimated by a French group: 2,400,000 curies I131 till March 22.

Testing milk and pasture for contamination?

Submitted by Milk drinker (not verified) on Sat, 2011-04-02 15:12.

I'm wondering if anyone in the Nuclear Engineering Department can advise me how to arrange for testing of samples of milk from my own cow (and perhaps from grass/soil from her pasture). I'm eager to come up with a plan to monitor contamination of my farm and its products. I don't have my own detection equipment, nor do I clearly understand how to quantify the long-term risks.

I am especially interested in understanding how much contamination, in the form of radionuclides, that I am taking into my body by consuming my own cow's milk. I typically drink about 6 liters/day.

Since the Fukushima meltdown, I've been supplementing my cow's diet with large quantities of clean kelp.

Thank You!

a little more perspective...

Submitted by Anonymous (not verified) on Sat, 2011-04-02 12:26.

Hiroshima: about 5,000,000 curies.

According to a weather

Submitted by Brian (not verified) on Wed, 2011-03-30 10:47.

According to a weather station in Berkeley, we have received 5.41 inches of rain since March 16th.

How about Oakley, CA? I live

Submitted by Anonymous (not verified) on Wed, 2011-03-30 12:04.

How about Oakley, CA? I live in Oakley, and it rained heavily.
thanks

Great, can you post the link

Submitted by Anonymous (not verified) on Wed, 2011-03-30 11:49.

Great, can you post the link to the weather station if there is a link? Thanks!

I'm glad everyone is

Submitted by dchivers on Wed, 2011-03-30 08:30.

I'm glad everyone is performing what I would call "back of the envelope" calculations. I warn of this type of estimation as there are many uncertainties between the observations on the ground and the real . We will be working out the total impact over the next few weeks given precip data from NOAA and the results of all of our measurements. Also, one cannot assume a constant concentration over the entire rainfall. Usually, the first part of the rain has higher concentration and this decreases as more rain comes at one time. We observe that some of our "spikes" of data came during times of off and on rain rather than a deluge. This is because the deluge tended to dilute the higher activity from the first part of the rain. This is a rather complex problem and I just warn on over-simplification. But kudo's to those trying to figure it out.

Is it possible that you'll

Submitted by Anonymous (not verified) on Wed, 2011-03-30 10:39.

Is it possible that you'll have to retract some prior statements made about our safety and the impact of the radioactive iodine and cesium that's fallen on California?

Anything is possible, but

Submitted by dchivers on Wed, 2011-03-30 12:16.

Anything is possible, but for now all indications are the risk to public health is small. There is a lot of conservation in our calculations.

depressing

Submitted by Anonymous (not verified) on Wed, 2011-03-30 05:48.

Hi:

these numbers are terribly depressing, in my opinion.
The health consequences won't be known for years.

Humbly, I-131 is not what

Submitted by Anonymous (not verified) on Wed, 2011-03-30 05:03.

Humbly, I-131 is not what should be concerning. By all means, stop eating milk products, filter your water and take necessary precautions. But, in two months it will all be gone.

Radiocesium on the other hand will be around for the next 30 years. Please update your calculations for this as well.

I am not certain about the

Submitted by Anonymous (not verified) on Wed, 2011-03-30 04:53.

I am not certain about the amount of rain. It could be 4 - 5 inches instead of 10 - 20, in which case the total release should be revised down to 430 Curies. Others with knowledge please confirm the rain level.

But in either case, the amount of I-131 that fell to the bay area with the rain alone is much larger than the total amount that was released in TMI. We are talking about 75 folds larger, if you take the 15 inch rain level, or 25 folds larger, if you take the 5 inch rain level.

The nanocuries is for per square meter, btw, the total amount is in curies.

Geez I wish I had a math brain. I just look at numbers and my head spins. Got A's in everything else though. Guess that doesn't help me now huh? lol

Chernobyl release 100,000,000 curies

Submitted by Raj (not verified) on Wed, 2011-03-30 00:25.

Apparently Chernobyl release 100,000,000 curies

http://hyperphysics.phy-astr.gsu.edu/hbase/nucene/cherno2.html