In order to confine radioactive materials inside the building, buildings, hot-cells and vessels are maintained at a lower air pressure than the atmospheric environment in Tokai Reprocessing Plant. For this purpose, air exhausters are continuously operated. However, during the periodic maintenance of the electric substation in September 2011, the incident in which the vessel ventilation including the spare machine of the highly radioactive liquid waste storage tank have not been started. In this paper, the c...
英字タイトル:
Improving the safety of the power supply system by separating the power supply circuit for control in the power distribution board in Tokai reprocessing plant

A leakage was found on the sea release pipe of the Tokai reprocessing plant The leak point was discovered in a part buried in the sea floor The damaged part was cut and was collected, and investigation into the cause was subsequently carried out As a result, external force and hydrogen embrittlement were estimated to be the cause that produced a crack on the pipe As restoration of the leak part, a construction method using a coupling technique was proposed considering steady sealability on the restore...
英字タイトル:
Liquid leakage from the sea release pipe of the Tokai reprocessing plant- Restoration of the leak point at the see release pipe --

There are plural facilities having a radiation controlled area in the Tokai reprocessing plant, and an interruptible power supply system which considered a blac kout is necessary for the power supply to eachility from the viewpoint of radiological management and nuclear material containment. In addition, at the ne of th e power supplying abnormality, intelligence gathering is necessary for prompt measures and toration. In this report, the intensive monitoring system, which aime d for the unification of the...
英字タイトル:
The construction of an intensive monitoring system for power supply stations in the Tokai reprocessing plant

Many facilities, in Tokai Reprocessing Plant, are necessary for safety aspects a s well as plant operation. It is essential to keep instruments running, especia lly for safety features such as ventilation system for sealing radio activities in the facility and cooling system for removing decay heat. The preventive main nance schedule for instruments of safety features was planned based on validity date of electric parts or decided with usage environment, working situation an recommended limit of time, in ...
英字タイトル:
Maintenance of electric parts in the Tokai Reprocessing Plant