Kansai Electric Power Co (Kepco) has acknowledged that lax management and an insufficient inspection regimen was a factor in a fatal steam pipe rupture last August its Mihama Plant in Mihamacho, Fukui Prefecture.

In a report to the Ministry of Economy, Trade and Industry, Kepco admitted that 42 items, including the pipe that ultimately failed, were dropped from inspection lists made for Kepco by Mitsubishi Heavy Industries Ltd (MHI) in 1990. The report revealed that Nihon Arm Co, a Kepco subsidiary, and MHI, initially in charge of inspecting the pipes, failed to include 27 pipes to be checked in that system.

The report goes on to say that communication between Kepco and Nihon Arm Co, which later took over the inspection work, was insufficient a reference to the fact that in 1997 Nihon reported that a section of pipe in the No. 4 reactor of the Takahama Plant in Takahamacho had not been included on an inspection list. The Kepco employee who received the notification failed to report it to a superior and this section was in the same location as the No. 3 Mihama reactor pipe which ruptured.