Last month, operators of the Tsuruga nuclear power plant in western Japan shut down the Unit 2 reactor after a small amount of radioactive gas was vented to the atmosphere. Today, we have more details about what caused the release.
The Mainichi Daily News reported yesterday:
The radioactive gas leak that occurred last month at a reactor of a nuclear power plant in Tsuruga, Fukui Prefecture, was caused by tiny holes in its piping, the plant’s operator Japan Atomic Power Co. said Friday.
The company said it had found 33 minute holes in the piping of the plant’s No. 2 reactor, which was halted after the level of radioactive substances in its primary coolant water increased sharply on May 2. A small amount of radioactive gas leaked from an exhaust pipe on May 8.
Owners of the plant had not inspected pipes at the plant since it opened, the Mainichi News reported:
Japan Atomic Power had not inspected or replaced the pipes in the No. 2 reactor facility since its operation began in 1987, company officials said. But they added that technical standards approved by the government did not require that the pipes be inspected.
The 33 holes were not the only leaks discovered:
In addition to the 33 holes in the piping for reducing the concentration of radioactive substances in coolant water, gas leaks were also confirmed at three joint sections, the officials said.