TOKYO — A Tokyo Electric Power Co. (TEPCO) employee testified in court here on April 10 that company executives decided to postpone tsunami prevention measures at the Fukushima No. 1 nuclear plant despite an assessment warning that a massive wave could hit the power station.
Since 2007, the male employee had been part of an internal assessment group tasked with estimating the maximum height of tsunami which could strike the Fukushima No. 1 plant.
The group commissioned a TEPCO-affiliated company to estimate the size of potential tsunami, based on a long-term assessment made by the government’s Headquarters for Earthquake Research Promotion that a massive wave could be generated by a quake in the Japan Trench, including off Fukushima Prefecture. In 2008, the TEPCO subsidiary reported that tsunami as tall as 15.7 meters could hit the plant.
In the trial, the employee stated, “I thought that TEPCO should take the assessment into consideration in taking (earthquake and tsunami) countermeasures, as the assessment was supported by prominent seismologists.” He said he was so confident that the utility would take action that he emailed another working group at the company, “There will definitely be major renovations at the Fukushima No. 1 and other plants.”
When the employee reported the assessment result to Muto, the then vice president gave him instructions that could be interpreted as an order to prepare to build a levee. However, the employee testified that Muto later shifted policy and called for an investigation into whether the long-term tsunami risk assessment is correct rather than taking tsunami countermeasures.
“I thought they (TEPCO) would consider taking tsunami prevention measures, but they changed policy unexpectedly and I lost heart,” the employee told the court.