Report 10/28/99 12:30
Sample of the solution in the precipitation tank taken on Oct. 20
According to the Science and Technology Agency (STA), on October 20, two officials from the STA accompanied JCO employees and collected a sample of the solution in the precipitation basin at the JCO uranium conversion plant in Tokai-mura. 50cc of the solution was taken and is currently being analyzed by the Japan Atomic Research Institute. According to a newspaper report, JCO employees had a drill at a warehouse liken to the JCO plant on Oct. 19 to prepare for the actual sampling project. The STA hopes to understand the amount of neutron produced during the accident and the scale of the accident by analyzing the fission products in the solution taken for sample. According to a newspaper report, tube was put into the precipitation basin and an electric motor was used to collect the solution into a glass bottle. The glass bottle was put into a container with three layers of lead to prevent radiation leak. Originally, it was planned to stir the solution before taking a sample to make the contents of the solution consistent. However, the equipment failed to operate, and the sample was taken from the untreated solution. According to a news paper report, the JCO employees involved in this sampling operation were exposed to 0.018 - 0.112 mSv of radiation.
According to the STA, 15 JCO employees were involved in the actual task of collecting the sample, and 14 other employees were involved in other tasks such as transporting the sample. STA commented that the employees were exposed to radiation of 112 microSv to 0, meaning no radiation was measured by the detector worn by the employees.