Japan's Nuclear Regulation Authority (NRA) launched an on-site inspection at the Japan Atomic Power Co's (JAPC) head office in Tokyo on 14 December after it was learned earlier this year that the firm rewrote data related to safety reviews necessary to restart Tsuruga 2 in Fukui Prefecture, The Mainichi reported.

NRA checked related documents and interviewed JAPC employees, based on nuclear regulation law. It is rare for the NRA to make an on-site inspection of a company over issues related to safety reviews, the paper noted.

There is an active fault directly beneath the Tsuruga 2 reactor building, which JAPC has denied, claiming that it is not an active fault line. If it is determined that the fault is active, JAPC will not be allowed to restart Tsuruga 2.

NRA had temporarily halted its safety review of the unit after finding 80 data alterations and deletions in documents related to the power plant's geological condition.