- High levels of radiation detected at 2 schools in Chiba Prefecture (Mainichi, Oct. 26, 2011):
ABIKO, Chiba — High levels of radiation have been detected on the premises of two elementary schools here, local education authorities have revealed.
According to the Abiko Municipal Board of Education, 11.3 microsieverts of radiation per hour was detected just above the surface of the ground near a ditch in the compounds of the Abiko Municipal Daiichi Elementary School on Sept. 15. The amount was 1.7 microsieverts in the air 50 centimeters above the ground.
Soil had piled up in the ditch, which had been damaged by growing tree roots, a situation similar to a residential area of the Chiba Prefecture city of Kashiwa where 57.5 microsieverts per hour was detected.
Radioactive cesium amounting to 60,768 becquerels per 1 kilogram of soil was found in the ditch.
The amount of radiation 50 centimeters above the ground had declined to 0.6 microsieverts per hour by Oct. 7 after the soil was removed.
The Education, Culture, Sports, Science and Technology Ministry pointed to the possibility that rain water contaminated with radioactive cesium overflowed from the ditch, soaked the nearby soil and accumulated in it.
At the Abiko Municipal Namiki Elementary School, 10.1 microsieverts per hour of radiation was detected near the surface of the ground where sludge removed from its swimming pool had been buried.
The school covered the area with a waterproof tarp and piled up dirt on the tarp to decrease the radiation emissions, after which 0.6 microsieverts per hour was detected 50 centimeters above the ground.
The two schools have sealed off the areas where high levels of radiation were detected.