TOKYO -- Tokyo Electric Power's so-called discovery, nearly five years after the fact, that it in fact had a manual for identifying meltdown at Fukushima Daiichi casts further doubt on the utility's credibility as it tries to restart its workhorse nuclear power plant.
"It's extremely unfortunate," Niigata Gov. Hirohiko Izumida said of Wednesday's revelation. Izumida will weigh whether to approve Tepco's request to restart reactor units 6 and 7 at the Kashiwazaki-Kariwa plant.
Izumida has been critical of Tepco's disclosure policy. It was at his administration's behest that the utility re-examined its handling of the Fukushima disaster, bringing a supposedly overlooked internal operation manual to light.
Tepco admitted that if it had followed the manual, it could have determined within days, rather than the two months it actually took, that meltdown had occurred.
Izumida lambasted Tepco President Naomi Hirose on this point last month, telling him that if Tepco was unaware of the meltdowns for two months, it was "not qualified to run a nuclear power plant."
Tepco applied in 2013 for the safety assessment needed to restart the Kashiwazaki-Kariwa reactors. Two years later, the Nuclear Regulation Authority decided that they would be the first reactors of the same design as the ruined Fukushima Daiichi units to undergo the assessment.
The process has entered the final stage. Earlier this month, the regulator concurred with Tepco's assessment that a fault below the seawall is inactive. The issue of whether the power station sits on active faults is one of the biggest considerations for Izumida's administration in deciding whether to approve the restart.
Tepco has stepped up its efforts to inform local residents of safety measures and other developments at the plant. Its review of the Fukushima response formed part of this outreach campaign, but ended up exposing the weakness of Tepco's accident preparedness at the time.
For a while after the disaster, all of Japan's nuclear reactors were off-line. Now, some are being restarted, with more making their way through the approval process.
Restarting units 6 and 7 at the Niigata plant would improve Tepco's annual cash flow by an estimated 120 billion yen ($1.07 billion) for each reactor. Anything that increases public doubts about the safety of nuclear power threatens this much-needed financial relief.