– Radioactive material in sludge at 16 prefectures (NHK, June 14, 2011):
NHK has learned that 16 prefectures in Japan have detected radioactive material in sludge since the crisis began at the Fukushima Daiichi nuclear plant in March.
NHK has found through interviews that at least 22 of Japan’s 47 prefectures have been testing sludge for radioactive material. 16 of them, ranging from Hokkaido to Osaka, have actually detected radioactive substances.
The level of radioactive cesium was highest in Fukushima city, at 447,000 becquerels per kilogram. This was followed by Tokyo at 55,000 becquerels and Maebashi, north of Tokyo, at 42,800 becquerels.
Rain-soaked soil containing radioactive substances has turned into contaminated sludge and is being stored at waste treatment plants.
Maebashi has designated area around its waste treatment plant a radiation danger zone, after radiation levels at 2 storage sites for incinerated sludge exceeded the government set-safety level.
Japan has had no safety guidelines for contaminated sludge, which is a new problem.
Last month, the government decided on an emergency measure to incinerate and store sludge that’s been found to contain 100,000 becquerels or more of radioactive materials.
But the measure applies only within Fukushima Prefecture, prompting other prefectures and municipalities to demand that the government quickly set guidelines on how to handle contaminated sludge.