Fukushima radiation spread to residential areas hours before venting

Radioactive material from the damaged Fukushima No. 1 Nuclear Power Plant spread to residential areas hours before workers vented the containment vessel of the plant's No. 1 reactor on March 12, 2011, to release pressure, it has emerged.

In one area, the level of radiation had surged to more than 700 times the normal level, indicating that many local residents were exposed to high levels of radiation before they evacuated.

The Fukushima Prefectural Government operated 25 monitoring posts around the nuclear power plant before it was crippled by the March 11, 2011 Great East Japan Earthquake and tsunami. Five monitoring posts were swept away by the tsunami, and 20 couldn't send data because the quake caused power cuts. Accordingly, officials were unable to put the data to use when evacuating residents. The Mainichi