Incinerator ash containing high levels of radioactive cesium is piling up in some municipalities around Tokyo as Kosaka, a town in Akita Prefecture that has one of the largest private-sector ash landfills in Japan, has shut its doors to ash from the metropolitan area since July.
Incinerator ash containing high levels of radioactive cesium is piling up in some municipalities around Tokyo as Kosaka, a town in Akita Prefecture that has one of the largest private-sector ash landfills in Japan, has shut its doors to ash from the metropolitan area since July.
Kosaka adopted the tough stance after it was revealed that ash containing levels of cesium exceeding the government-set limit shipped from the city of Matsudo, Chiba Prefecture, had been buried at its landfill without notice.
Matsudo and other local governments in the metropolitan area had been shipping tons of ash produced from garbage-burning incinerators annually to the disposal facility in Kosaka. But they are now stuck with growing amounts of radioactive ash.
The ash woes for the cities started on July 11, when ash at a garbage disposal facility in Matsudo was found to contain 10,500 becquerels of radioactive cesium per kilogram, higher than the legal limit for landfill ash at that time, which was 8,000 becquerels per kilogram.
The Matsudo municipal government informed Kosaka of the fact and stopped the shipment of ash from the disposal facility but didn't take steps to prevent the disposal of ash already on its way to the northern town, being transported on a freight train.
As a result, some 40 tons of contaminated ash was buried at the landfill in Kosaka, including ash produced after Matsudo started radiation checks on incinerator ash.
On Aug. 3, Kosaka notified Matsudo of its decision to rescind the agreement between them on the use of the town's landfill to dispose of incinerator ash from the city. The town in Akita Prefecture bitterly criticized Matsudo's handling of the problem as "an extremely deplorable response that makes light of the responsibility of a local community that produces ash."
On Aug. 8, Kosaka sent back the remaining ash from Matsudo that had been left at East Japan Railway Co.'s Odate Station in the city of Odate, Akita Prefecture.
By July 13, Tokyo-based Dowa Holdings Co. group, which operates the landfill, notified the dozen or so local governments in the Tokyo metropolitan area of the suspension of the disposal of ash from their incinerators, according to the Kosaka municipal government.
Kosaka, where about 6,000 people live, once prospered as a mining town. The landfill has the capacity of taking 2.7 million cubic meters of incinerator ash.
The landfill was created in 2004 by Dowa, which is historically linked with the now-defunct operator of the Kosaka mine. Currently, the landfill accepts some 65,000 tons of incinerator ash annually from some 30 local governments across the nation.
Kosaka has been promoting itself as an environmentally conscious town by pouring a lot of energy into establishing a resource recycling system based on mining technology. The town sees the news about cesium-polluted ash as a potentially serious blow to its green reputation.
Kosaka's government was especially concerned that the revelation could generate harmful rumors that hurt the sales of the town's specialties. Rapeseed oil and the "momobuta (peachy pig)" brand of pork produced in the town have gained in popularity thanks to successful sales promotion efforts focused on their eco-friendliness. Another important revenue source for the local community that could be damaged by cesium-related rumors is Korakukan, a wooden theater that attracts 80,000 visitors every year.
On Sept. 2, Kosaka's government approved the resumption of disposal of ash from the municipalities around Tokyo at the landfill after Dowa submitted a plan for preventing contaminated ash from ending up in the facility. The plan requires the operator and the local governments concerned to measure the levels of radiation contained in ash when it is shipped from incineration facilities and arrives at the landfill.
But the decision has been met with resistance. Some members of the town assembly criticized the municipal government's move as "too hasty."
In response, the town's government started on Sept. 13 meetings with local residents to explain about the decision.
Many local residents appear to remain worried and resentful about the polluted ash. Some people in the town are considering moving out, while others are asking the town's government why it has decided to restart accepting ash in such haste.
Meanwhile, Matsudo has found itself in a serious bind. The city of some 480,000 people, which has grown as a bedroom community for people working in Tokyo, has been shipping incinerator ash to the town in Akita Prefecture since 2005.
The city planned to use the landfill in Kosaka to dispose of about half of an estimated 15,700 tons of ash expected to be produced by burning garbage in the current fiscal year.
Since Kosaka decided to refuse to dispose of ash from Matsudo, the city has been shipping most of ash that is not dangerously contaminated with radiation to other landfills.
But some 52 tons of ash containing high levels of radioactive cesium are left at two incineration facilities in the city, with no prospect of disposal. In addition, their amounts are increasing gradually.
The city of Nagareyama, also in Chiba Prefecture, is facing the same problem. Some 360 tons of polluted ash are left at incineration facilities within the city.
Both cities have taken measures to prevent the release of radioactivity from the ash into the environment.
With the capacity of keeping polluted ash at these facilities approaching its limit, the Environment Ministry decided at the end of August on new safety guidelines concerning disposal of such ash. Under the new guidelines, incinerator ash containing up to 100,000 becquerels of cesium can be buried at a landfill if measures are taken to prevent radioactivity from seeping into underground water, such as mixing the ash with cement.
But this approach doesn't offer a solution to the problem unless there are local communities with ash landfills that are willing to accept radioactive ash solidified with cement.
Matsudo is now looking for such local communities, pledging to establish rules that will make sure that a similar mix-up will not happen again.
The city of Saitama had been shipping 12,000 tons, or over 30 percent, of incinerator ash produced annually at its incineration facilities and disposed at landfills, to Kosaka.
For the time being, that amount can be buried at disposal sites within the city, according to the municipal government. But officials at the government are concerned about the possibility of the situation remaining unsolved for the long term.
(This article was written by Shintaro Egawa and Jiro Sonoda)