東海再処理施設における海中放出管からの漏えいについて; 海中放出設備及び漏えい事象概要(可能性から確認)

Liquid leakage from the sea release pipe of the Tokai reprocessing plant; Summary of ocean-releasing facilities and the leak phenomenon (Confirmation based on the possibility)

野口 浩二; 安尾 清志 ; 瀬戸 信彦; 岩崎 省悟; 伊波 慎一

Noguchi, Koji; Yasuo, Kiyoshi; Seto, Nobuhiko; Iwasaki, Shogo; Inami, Shinichi

東海再処理施設の低放射性廃液は、海中放出設備により海洋放出を行っている。この海中放出設備に漏えいがあることが確認され、点検・調査を行い漏えい箇所の特定をし、漏えい箇所を切断・回収して、原因調査を行った。その結果、漏えいの原因は、配管の損傷と、損傷箇所に経年的な変化が生じたことにより漏えいに至ったと推定した。この漏えい箇所は原因調査作業を踏まえ再発防止対策を講じ、復旧作業を行った。本件では、漏えいを生じた海中放出管を含む海中放出設備の概要,発生の状況,漏えい箇所を確認した経緯(点検・調査)について報告する。

At the Tokai reprocessing plant, release of the low radioactive fluid to the ocean is carried out using sea release facilities. It was confirmed that there was a leak point on the sea release facilities. Therefore, check and investigation were performed and the leak point was identified. The leak part was cut and the part was then collected to investigate the cause of the leak. As a result, it was estimated that the leak occurred after the pipe was mechanically damaged and a successive change occurred on the part. For this leak point, a series of works for the cause investigation was carried out in detail, the repair work was performed, and preventive measures were taken against recurrences. This paper describes the summary of the sea release facilities, the situation of the outbreak of the leak, and the process that confirmed the leak point.