Radioactive sewage sludge is quickly filling up treatment facilities in eastern Japan as recycling companies have refused to accept it for safety reasons.
Radioactive sewage sludge is quickly filling up treatment facilities in eastern Japan as recycling companies have refused to accept it for safety reasons.
The central government, which has only presented guidelines for temporary storage, plans to set standards on final disposal.
Radioactive cesium was first detected in sludge at a sewage treatment facility in Koriyama, Fukushima Prefecture, on May 1.
Radioactive sewage sludge has since turned up at facilities in Tokyo, Kanagawa, Saitama and other prefectures.
Officials believe that radioactive materials from the Fukushima No. 1 nuclear power plant flowed into sewage pipes with rainwater and were condensed during sewage treatment.
In normal times, about 80 percent of sewage sludge nationwide is recycled into cement and fertilizers after it is incinerated into ash.
But at the Iriezaki Centralized Sludge Treatment Center in Kawasaki, about 220 tons of incineration ash in 550 double-layered bags have been piled up on the passageway and elsewhere.
Director Takashi Ookouchi said the center will run out of storage space in a few days.
An inspection on May 13 found 470 becquerels of radioactive cesium per kilogram of sewage sludge and 13,200 becquerels per kilogram of incineration ash.
A local company that reuses ash for cement said it will not take it until safety is confirmed.
At a sewage treatment facility in Tachikawa, western Tokyo, bags of incineration ash occupy half of an underground warehouse.
A cement company has refused to accept it since radioactive cesium and iodine were found from sludge and ash.
Toshiyuki Hattori, chief of the sewage treatment plant, said the storage space will run out at the end of June.
In Ibaraki Prefecture, radioactive sludge has been found at all of its eight sewage treatment facilities, and shipments have been suspended.
Concerns are growing among workers and residents about health effects.
The city of Chichibu and three neighboring towns in Saitama Prefecture submitted an emergency request to Governor Kiyoshi Ueda on June 3 to demand the central government set specific disposal standards.
The Chichibu municipal government also ordered protective clothing for workers at sewage treatment facilities.
The city of Saitama will post on its website results of inspections at sewage facilities, while the Saitama prefectural government will place dosimeters at sewage facilities.
The Tokyo metropolitan government decided in May to bury incineration ash from its 23 wards at a disposal facility in Tokyo Bay.
Ash was mixed with cement and covered with soil, but the amount of radiation at the site was three to eight times larger than in Shinjuku Ward on May 25.
In late March, 170,000 becquerels of radioactivity was detected in 1 kilogram of incineration ash at a sewage treatment facility in Koto Ward, and radioactive materials were also found at other facilities.
At that time, the metropolitan government shipped the ash for recycling because the central government did not have guidelines.
The Nagano prefectural government is worried because cesium was found in incineration ash at a sewage facility in Suwa.
The prefecture has been selling the ash, which contains a high concentration of gold, for the past three years, raising tens of millions of yen annually.
It is not clear where the gold came from. One theory is that elements from a nearby gold vein flow into hot spring water and find their way into sewage pipes.