Hot spot decontaminated at Tokyo primary school

The Yomiuri Shimbun

Workers remove soil during decontamination work at Higashi-Fuchie Primary School in Adachi Ward, Tokyo, on Tuesday.

Soil around a small "hot spot" detected at a primary school in Tokyo was removed Tuesday, as the local ward office started measuring radiation levels at hundreds of other facilities it operates.

A radiation level of 3.99 microsieverts per hour was detected under a drainpipe at Higashi-Fuchie Primary School in Adachi Ward on Monday, but this figure dropped to 0.15 microsieverts per hour after the soil was removed, according to ward officials.

Soil to a depth of 10 centimeters in a one-square-meter area around the drainpipe was removed, put in a bag and buried in a hole 1.2 meters deep at a different location at the school.

Tests conducted under the drainpipe after the soil was removed detected 0.15 microsieverts per hour at a depth of five centimeters, and 0.13 microsieverts per hour at depths of 50 centimeters and one meter.

Ward officials said these radiation levels do not pose any health risks to humans. The area, which was next to the school's swimming pool, is no longer off-limits.

Meanwhile, the Adachi Ward Office on Tuesday began measuring radiation at about 800 facilities it operates, including nurseries as well as primary and middle schools. These tests will focus on gutters and areas under drainpipes where contaminated rainwater could accumulate and cause high radiation levels.

If a radiation level of 0.25 microsieverts per hour is detected at a height of 50 centimeters, the ward will remove soil around the spot or wash it with high-pressure water, ward officials said.