One thing that puzzles me is how much variability there is in local background radiation. I bought a Geiger counter about a year ago just to see if the people saying the whole west coast was being fried (it isn't) by Fukushima. At the time typical back ground was 13 microseiverts / hour. Today is only 10, and I let it run for a while because there is some randomness but it stayed consistently low tonight.
