Government Run Map: EPA's RadNet Air Monitoring Data (Updated "continuously.") This EPA map seems to be experiencing difficulties. Could be:
EPA Press Release from Sunday, March 27, 2011:
"As a result of the incident with the Fukushima nuclear plant in Japan, several EPA air monitors have detected very low levels of radioactive material in the United States.Did they mean to say "below" background levels?
There have been reports received that the states of Pennsylvania and Massachusetts have seen elevated levels of radiation in recent precipitation events. EPA is reviewing this data – however, in both cases these are levels above the normal background levels historically reported in these areas."
Privately Run Map: Radiation Network, a "nationwide grass roots effort to monitor the radiation in our environment." Run by Mineralab who sells the geiger counters if you want to take part. (Updated every minute.)