Monday, April 4, 2011

More short half life radioactive fallout rains on Saint Louis Missouri 4/4/11

I followed up the 3am rainstorm Geiger counter readings from this morning by retaking readings from the same samples; and by taking readings from rain water collected after the 3am reading. In a span of seven hours the readings dropped from 0.034 mR/hr to levels undetectable above background. The limited granularity of this data and the probabilistic uncertainty of half lives prevent any accurate quantitative calculations of the half life of these samples; the best one can say is that the half life is short. Based on the much hotter readings I received from the 3/29/11 rainstorms, I believe that this is the same fallout contaminant with a half life of less than 18 hours.

The short half life of the this radioactive fallout is quite concerning because it is an indicator that the radiation levels where MUCH HIGHER for people receiving rain fall from the same source a few days earlier. The short half life would result in significant under reporting of the threat in water contamination tests like ASTM D3648, or in the sampling checking for radioactivity in the milk supply. These tests are NOT suitable canaries in the coal mine for this type of short half life fallout, especially if the fallout is Iodine 123 as I suspect. Thyroid examination of cows producing radioactive milk would make for a much more sensible "canary". With the short half life'd fallout, The threat and risks of significant thyroid damage increase as as one moves towards the west coast and Hawaii. (click here for an alternate/simultaneous, more complex and more uncertain risk model)

The true risk of injury from this short half life fallout would be based on an unknown fallout distributions and local weather events. The significance of that statement is that from a "greater good" public health, safety, and economic perspective; I expect some would argue it is better to keep people in the dark than risk panic. The word Tornado was once banned from weather reports for the same reason.

1 comment:

  1. Wow seeing short half-life rain fallout in Colorado too. Thanks for the post. I saw 2.56micro-sieverts/hour on wipes from my solar panels kust after storm. My meter characterizes anyrhing over 1.2 as "dangerous radiation". This primarily was gamma ray too.