Detection of Radioactive Material from RDF Incineration Ashes at Chugai?s Fuji-Gotemba Research Laboratories
August 19, 2011 (Tokyo) - As a part of its contribution to the
local community, Fuji-Gotemba Research Laboratories located in
Gotemba City, Shizuoka Prefecture of Chugai Pharmaceutical Co.,
Ltd. [Head Office: Chuo-ku, Tokyo; President: Osamu Nagayama
(hereafter, “Chugai”)] purchases RDF chips (solid fuel
made from non-industrial wastes), from the local RDF center
operated by Gotemba City, Oyama Kouiki Gyousei Kumiai (hereafter,
“Kumiai”). These chips are incinerated by the
Laboratory’s RDF dedicated steam boilers (hereafter,
“RDF boilers”) to use the steam power as a source of
energy consumed within the Laboratory. Chugai has been informed by
the Kumiai that although the value is significantly lower than the
reference value, radioactive cesium has been detected from the
incinerated ash of RDF chips.
After radioactive cesium (cesium-134 and -137) was detected in high
concentration in fly ash emitted from a non-industrial waste
incineration plant in Tokyo in June this year, the Government of
Japan required local governments in 15 prefectures, including
Shizuoka Prefecture to measure the level of radioactive cesium in
incinerated ash generated from non-industrial waste incineration
plants.
To respond to the requirement, in July, the Kumiai made a
voluntarily analysis of incinerated ash emitted from the RDF
boilers of Chugai’s Fuji-Gotemba Research Laboratories, a
major consumer of RDF chips. As a result, radioactive cesium was
detected from the incinerated ash of RDF chips at a level far below
the reference value set out for soils used for land disposal, which
is 8,000 Bq/kg or below.
Currently, the RDF boilers are not in operation and Chugai is in
discussion with the Kumiai regarding the future utilization of
these boilers.
?Measurement
Data?
?Bq/Kg?
|
Cs-137 |
Cs-134 |
Total for Cs |
|
|
Incinerated ash |
120 |
110 |
230 |
|
Fly ash |
230 |
210 |
440 |
?Specimen sampled on: July 8?
?Note?
- RDF (Refuse Derived Fuel): a type of solid fuel
made from household waste, crashed, dried and compacted after
adding lime, etc.
- Fly ash means ash contained in emission gas collected by
filters.
- Incinerated ash and fly ash with cesium concentration of 8,000
Bq/kg or below may be disposed by reclamation at the final disposal
place. (Notice from the Ministry of Environment dated June 28, 2011
titled ‘Measurement and Temporary Handling of Incinerated Ash
at Non-Industrial Waste Incineration Plants’)
- Indices on intake limitation of vegetables, crops, meat, eggs,
fishes and other foods:
Cesium concentration of 500 Bq/kg or below (Pharmaceutical and Food
Safety Bureau, MHLW dated March17, 2011)
Posted: August 2011
