Safecasting inside the evacuation zone

If you’ve been following our measurements and discussions surrounding them, you know we’ve been saying that the decision to evacuate people in a set radius from the Fukushima Daiichi plant is flawed. Wind, weather, topography and many other factors ensure that radiation isn’t higher the closer you get to the plant, and lower further away, rather it’s higher in areas that had more fallout. We’ve measured some very high readings outside of the mandatory evacuation zones but until recently haven’t been able to get inside of the exclusion zone. Earlier this week a safecast volunteer was able to get inside with a bGeigie and took these readings. We’re excited to have this data finally and as you can see some of the areas that are much closer to the plant have lower radiation levels than some further away.

This is important because it’s possible that some people were evacuated from areas with relatively low levels into areas with higher levels. Radius exclusion zones are useless for this kind of event, and are really only useful if the goal is to get people out of an area where future incidents may occur. Accurate mapping of the area, and a functional sensor network would have shown what areas were actually contaminated rather than the current speculation. We hope to have more of this data soon, but in the meantime this is a fantastic bit of information to be able to reference.

Here are some other relevant maps:

About the Author

Sean Bonner


Sean Bonner is a co-founder and Global Director of Safecast. Based in Los Angeles, he's an Associate Researcher at the Center For Civic Media at the MIT Media Lab and a Shuttleworth Fellow.