TOKYO -- More than five years after the Fukushima nuclear disaster, another inconsistency in Tokyo Electric Power Co. Holdings' version of the truth has surfaced, as a company official said during an interview Monday that he was aware of guidelines defining a meltdown at the time of the accident.
The operator of the Fukushima Daiichi nuclear plant said in February that it could have told the public by March 14, 2011 -- just days after the March 11 earthquake and tsunami -- that the power plant had suffered meltdowns if staff had followed the company's disaster management guidelines correctly. Instead, the company, known as Tepco, refused until May of that year to acknowledge that the tsunami had caused meltdowns at the plant's Nos. 1-3 reactors.
The heart of the issue is Tepco's claim that its staff overlooked an entry in the guidelines that a reactor should be deemed to have suffered a meltdown if 5% or more of its fuel rods are believed to have been damaged.
During the Monday interview, a reporter asked company official Yuichi Okamura whether he was unaware of the 5% rule at the time of the disaster.
"I had known about it through my years of work in the field," Okamura replied.
But Okamura also noted he "was not in the position to judge whether a meltdown occurred" because his job was to deal with the disaster, including efforts to ensure the No. 4 reactor's spent fuel rod cooling pool received a steady supply of water.
This was the first time a company official acknowledged being aware of the 5% rule at the time of the incident. This revelation might be seen as evidence to discredit Tepco's explanation of why it took the company two months to acknowledge that meltdowns had occurred.
The company was known as Tokyo Electric Power Co. at the time of the disaster but transitioned to a holding company structure on April 1.