Japan’s science ministry conducted helicopter surveys of radiation, covering 22 prefectures in eastern and central Japan.  They found that long lasting cesium is contaminating a large area.

The highest level of cesium contamination is around the Fukushima Daiichi nuclear plant, with some areas hitting more than one million becquerels per square meter!

The scientists also found that the mountain ranges nearby have been blocking a lot of cesium from spreading further south.  As a result, geographic regions about 60 kilometers (37 miles) to the north, and about 200 kilometers (124 miles) southwest, are contaminated with more than 30,000 becquerels per square meter.

They say the cesium contamination will last decades.  And remember, the Fukushima Daiichi disaster reactors are still emitting lots of radiation!