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Latest Radiation (Water, Milk, Air) Measurements from California

With all questions surrounding the amount of radiation being measured in California, I thought you all might find this site useful:


"Iodine-131 is detected at lower levels than previously measured, but Cs-134 and Cs-137 are now being detected as well. We are interested in watching these trends in the coming days, so we will continue monitoring the milk levels."

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for the bump.

Hopefully this helps to balance out the hysteria about this issue.


I live in the area. This confirms what I had assumed.

"Response to some misleading claims about our measurements

"Some claims have been made recently that our data shows that Bay Area water exceeds EPA regulations by a factor of 181 -- sometimes this has been reported as 18,100% higher, or erroneously as a factor of 18,100 higher. This claim is misleading. Specifically, the reports refer to the I-131 activity of 20.1 Bq/L measured in rainwater on 3/23. The EPA limit for I-131 is 3 pCi/L, or 0.111 Bq/L. There are a number of things wrong with this claim.

"First, the measurement we made was of rainwater, not drinking water, so the drinking water limit does not apply. We instead should be discussing tap water, in which we detected a small amount of I-131 (0.024 Bq/L). This is a factor of almost 1,000 below the rainwater measurement and a factor of 4.6 below the EPA limit.

"It should also be noted that the EPA limit assumes the water is ingested over the course of an entire year. That is, someone drinking 3 pCi/L water for an entire year would reach the EPA dose limit of 4 millirem, which is a very small dose. The tap water measurement of 0.024 Bq/L on 3/29 is our only detection of I-131; on subsequent days it could not be detected, probably due to the radioactive decay of I-131. So this tap water could have been ingested for at most 1 day, giving the public a dose 365 times smaller than if one assumes an entire year of ingestion. That means the tap water is effectively a factor of 1,700 below the EPA limit.

"Finally, we believe that the clear decay in all isotopes shown in our air filtration measurements is an indication that water activity levels are declining at least for now."

Ĵīɣȩ Ɖåđşŏń

"Fully half the quotations found on the internet are either mis-attributed, or outright fabrications." - Abraham Lincoln

Let's also discuss how these limits were

arrived? These limits are purely guesses from the 40's, 50's and 60's when they were doing nuclear bomb tests if I am correct.
and then you have this....

ok, I will.

they were derived from measuring the intensity of the discharge.
before we can go there, we need to understand Radiant. think of it as why your ass gets cold standing around a campfire.

ytc's picture

Thanks, chopinwood.

UC Berkeley, Dept of Nuclear Engineering: a good research center to bookmark for a quick reference.