IAEA Confirms Very High Levels of Contamination Far From Reactors, All Things Nuclear via Union of Concerned Scientists (UCS), March 30, 2011:

Today the IAEA has finally confirmed what some analysts have suspected for days: that the concentration per area of long-lived cesium-137 (Cs-137) is extremely high as far as tens of kilometers from the release site at Fukushima Dai-Ichi, and in fact would trigger compulsory evacuation under IAEA guidelines. …

[I]t is now abundantly clear that Japanese authorities were negligent in restricting the emergency evacuation zone to only 20 kilometers from the release site.

Other UCS Facts:

• 40 km away from Fukushima Daiichi in Iitate, there where soil concentrations of Cs-137 at levels up to 3.7 megabecquerels (MBq/sq. m.)
• Soviets set compulsory relocation level at 1.48 MBq/sq. m. after Chernobyl
• Far higher than previous IAEA reports of values of Cs-137 deposition
• Comparable to the total beta-gamma measurements reported previously by IAEA