It's raining now (on 4/8) here in Pennsylvania, and after wiping off the hood of my car with a paper towel I'm getting 5x the background count using a pancake geiger tube. Over a 3hr. period I watched the reading drop from 250 counts/minute down to about 50 counts/min.(normal background). The readings drop too quickly to be due to decay or half-life. Possible explanation: It could be nuclides like Iodine131and Xenon133 in gassous form dissolved in the water, and evaporating away with it.
Below is a reply I received to my youtube video of the 3/29/11 fallout rain
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It's raining now (on 4/8) here in Pennsylvania, and after wiping off the hood of my car with a paper towel I'm getting 5x the background count using a pancake geiger tube. Over a 3hr. period I watched the reading drop from 250 counts/minute down to about 50 counts/min.(normal background). The readings drop too quickly to be due to decay or half-life. Possible explanation: It could be nuclides like Iodine131and Xenon133 in gassous form dissolved in the water, and evaporating away with it.