Let's get this disclaimer out of the way first: Radiation levels in the U.S. from the unfolding nuclear disasters in Japan are way below any unhealthful level. That said, the spike in radiation -- even with "not unhealthful" levels -- in Massachusetts is intriguing.
Check out this EPA RadNet chart showing the levels post-Japan earthquake (click for larger image):
If you're like me, perhaps you heard the story and figured the radiation got up into the atmosphere and floated across the U.S. to Massachusetts, in which case Minnesota probably would've gotten a little too, right? It doesn't appear so. The EPA monitor near the metro is out of order, but here's Duluth's:
To the west of us, here's Bismarck:
The EPA says Massachusetts and Pennsylvania are the areas where radiation spiked, probably because of rain:
While short-term elevations such as these do not raise public health concerns - and the levels seen in rainwater are expected to be relatively short in duration - the U.S. EPA has taken steps to increase the level of nationwide monitoring of precipitation, drinking water, and other potential exposure routes to continue to verify that.
Saying that radiation levels "are way below any unhealthful level", is bound to get you kicked out of the sensationalist media club...
Radiation in the atmosphere probably looked down on the mid-west from way up there and assumed it was already a wasteland, moved on to a more attractive target.
Interesting. i have been taking readings almost every day in Delano Mn and they reflected the MA readings - Higher when the rain came. But, the last several days it has been a little higher than normal. Normal has been .1 microseiverts and it is currently .12. It has gone as high as .13 when it rained. Although too low to be of concern, the 20-30% increase is definitely noticeable. I have not yet taken readings today (March 31, 2011). I am normally not distrustful of the government, but with their readings not reflecting mine I have got to wonder. Maybe their equipment isn't as sensitive as mine, or maybe its more accurate, or maybe the data is being censored.