Dr. Tsubokura's Radiation Lecture Vol.66
Author: Masaharu Tsubokura
Editors: Akihiko Ozaki M.D., Yuki Senoo
131. Fire accident at the nuclear weapons manufacturer
In the past, radiation exposure has occurred on several occasions, including the dropping of atomic bombs on Hiroshima and Nagasaki during World War II, atmospheric nuclear tests, and accidents at nuclear processing facilities and power plants. In fact, the Chernobyl, Three Mile Island, and Fukushima Daiichi nuclear power plants are not the only ones that have had accidents involving reactors.
On October 10, 1957, a major fire broke out at the nuclear reactor at the Windscale nuclear facility (now Sellafield) in Cumbria, England, causing significant radioactive contamination in the surrounding environment. This accident was rated as a level 5 accident on the International Nuclear Event Scale, which has a maximum level of 7.
At that time, this reactor was operating to produce fissile materials for nuclear weapons and not as a power generator. It has been estimated that the radioactive iodine and cesium released into the environment in this accident were about one-thousandth to one-hundredth of those chemicals disseminated in the Fukushima Daiichi nuclear power plant accident. However, following the 1957 accident, radioactive substances were repeatedly released at the Windscale nuclear facility.
A variety of nuclear facilities, which includes not only power plants but also nuclear fuel reprocessing facilities, are currently in operation all over the world, and Japan is no exception. Regarding their activities, discussions between those facilities’ companies and local community members continue to this day.
132. Radioactive wastes used to be poorly handled
In the past, radiation exposure has occurred on several occasions, including the dropping of atomic bombs on Hiroshima and Nagasaki during World War II, atmospheric nuclear tests, and accidents at nuclear processing facilities and power plants. In fact, the Chernobyl, Three Mile Island, and Fukushima Daiichi nuclear power plants are not the only ones that have had accidents involving nuclear reactors.
On 29 September, 1957, the Kyshtym disaster occurred at the Mayak nuclear materials production facility in Chelyabinsk Oblast in the former Soviet Union. In this accident, a tank containing radioactive residues overheated and exploded, resulting in severe radioactive contamination of the surrounding environment. The disaster was rated as a level 6 accident on the International Nuclear Event Scale, placing higher on it than the Three Mile Island accident (Level 5), and is said to be the third-worst nuclear accident in history.
To compete with the United States, the former Soviet Union in 1948 developed and started the operation of a nuclear processing facility to produce fissile materials for nuclear weapons. Unlike in the present day, radioactive wastes were poorly handled back then, as large quantities of waste products were discharged into the Techa River and nearby lakes. Therefore, residents living in the area along Techa River were exposed to contaminated water and food even before the accident in 1957.
It has been reported that the exposure doses received by residents due to the Mayak nuclear complex’s series of radioactive pollution were significantly higher than doses received by residents near the Fukushima nuclear accident. The Techa River was also highly contaminated by strontium, which is another remarkable characteristic of the negative health effects caused by the Mayak incident that distinguishes it from other nuclear accidents.
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The Japanese version of the manuscript was originally published in Fukushima Minyu, a local newspaper in Fukushima prefecture, Japan, on 16th and 23rd July 2017 was reproduced for MRIC Global under the author's permission.